meson: Add predefined macro -D__MSVCRT_VERSION__=0x0700 only in mingw environment without _UCRT

Fixed the following error:
```

1 error generated.
[18/1468] Compiling C object src/util/libmesa_util.a.p/half_float.c.obj
FAILED: src/util/libmesa_util.a.p/half_float.c.obj
"cc" "-Isrc/util/libmesa_util.a.p" "-Isrc/util" "-I../../src/util" "-Iinclude" "-I../../include" "-Isrc" "-I../../src" "-Isrc/mapi" "-I../../src/mapi" "-Isrc/mesa" "-I../../src/mesa" "-I../../src/gallium/include" "-Isrc/gallium/auxiliary" "-I../../src/gallium/auxiliary" "-IC:/CI-Tools/msys64/clang64/include" "-fvisibility=hidden" "-fcolor-diagnostics" "-D_FILE_OFFSET_BITS=64" "-Wall" "-Winvalid-pch" "-std=c11" "-O2" "-g" "-D__STDC_CONSTANT_MACROS" "-D__STDC_FORMAT_MACROS" "-D__STDC_LIMIT_MACROS" "-DPACKAGE_VERSION=\"22.1.0-devel\"" "-DPACKAGE_BUGREPORT=\"https://gitlab.freedesktop.org/mesa/mesa/-/issues\"" "-DHAVE_WINDOWS_PLATFORM" "-DHAVE_SURFACELESS_PLATFORM" "-DUSE_ELF_TLS" "-DUSE_TLS_BEHIND_FUNCTIONS" "-DENABLE_ST_OMX_BELLAGIO=0" "-DENABLE_ST_OMX_TIZONIA=0" "-DEGL_NO_X11" "-DHAVE___BUILTIN_BSWAP32" "-DHAVE___BUILTIN_BSWAP64" "-DHAVE___BUILTIN_CLZ" "-DHAVE___BUILTIN_CLZLL" "-DHAVE___BUILTIN_CTZ" "-DHAVE___BUILTIN_EXPECT" "-DHAVE___BUILTIN_FFS" "-DHAVE___BUILTIN_FFSLL" "-DHAVE___BUILTIN_POPCOUNT" "-DHAVE___BUILTIN_POPCOUNTLL" "-DHAVE___BUILTIN_UNREACHABLE" "-DHAVE___BUILTIN_TYPES_COMPATIBLE_P" "-DHAVE_FUNC_ATTRIBUTE_CONST" "-DHAVE_FUNC_ATTRIBUTE_FLATTEN" "-DHAVE_FUNC_ATTRIBUTE_MALLOC" "-DHAVE_FUNC_ATTRIBUTE_PURE" "-DHAVE_FUNC_ATTRIBUTE_UNUSED" "-DHAVE_FUNC_ATTRIBUTE_WARN_UNUSED_RESULT" "-DHAVE_FUNC_ATTRIBUTE_WEAK" "-DHAVE_FUNC_ATTRIBUTE_FORMAT" "-DHAVE_FUNC_ATTRIBUTE_PACKED" "-DHAVE_FUNC_ATTRIBUTE_RETURNS_NONNULL" "-DHAVE_FUNC_ATTRIBUTE_ALIAS" "-DHAVE_FUNC_ATTRIBUTE_NORETURN" "-DHAVE_FUNC_ATTRIBUTE_VISIBILITY" "-DHAVE_UINT128" "-D_WINDOWS" "-D_WIN32_WINNT=0x0A00" "-DWINVER=0x0A00" "-DPIPE_SUBSYSTEM_WINDOWS_USER" "-D_USE_MATH_DEFINES" "-D__MSVCRT_VERSION__=0x0700" "-DUSE_SSE41" "-DUSE_GCC_ATOMIC_BUILTINS" "-DHAS_SCHED_H" "-DHAVE_CET_H" "-DHAVE_STRTOF" "-DHAVE_TIMESPEC_GET" "-DHAVE_STRTOK_R" "-DHAVE_QSORT_S" "-DHAVE_ZLIB" "-DHAVE_ZSTD" "-DHAVE_COMPRESSION" "-DLLVM_AVAILABLE" "-DMESA_LLVM_VERSION_STRING=\"13.0.1\"" "-DLLVM_IS_SHARED=1" "-DDRAW_LLVM_AVAILABLE" "-DMESA_EXECMEM" "-DVK_USE_PLATFORM_WIN32_KHR"
"-Werror=implicit-function-declaration" "-Werror=missing-prototypes" "-Werror=return-type" "-Werror=empty-body" "-Werror=incompatible-pointer-types" "-Werror=int-conversion" "-Wimplicit-fallthrough" "-Wno-missing-field-initializers" "-fno-math-errno" "-fno-trapping-math" "-Qunused-arguments" "-fno-common" "-Wno-microsoft-enum-value" "-Werror=format" "-Wformat-security" "-Werror=thread-safety" "-ffunction-sections" "-fdata-sections" "-pthread" "-Werror=pointer-arith" "-Werror=gnu-empty-initializer" -MD -MQ src/util/libmesa_util.a.p/half_float.c.obj -MF "src/util/libmesa_util.a.p/half_float.c.obj.d" -o src/util/libmesa_util.a.p/half_float.c.obj "-c" ../../src/util/half_float.c
In file included from ../../src/util/half_float.c:30:
In file included from ../../src/util/half_float.h:32:
In file included from ../../src/util/u_cpu_detect.h:41:
In file included from ../../src/util/u_thread.h:35:
In file included from ../../include/c11/threads.h:64:
../../include/c11/threads_win32.h:136:5: error: implicit declaration of function 'timespec_get' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
    timespec_get(&now, TIME_UTC);
    ^
```

Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14014>

meson.build

@@ -1102,7 +1102,18 @@ elif host_machine.system() == 'windows'
       '-DNOMINMAX',
     ]
   else
-    pre_args += ['-D__MSVCRT_VERSION__=0x0700']
+    # When the target is not mingw/ucrt
+    # NOTE: clang's stddef.h are conflict with mingw/ucrt's stddef.h
+    # So do not include headers that defined in clang for detecting
+    # _UCRT
+    if cc.compiles('''
+      #include <string.h>
+      #if defined(__MINGW32__) && defined(_UCRT)
+      #error
+      #endif
+      int main(void) { return 0; }''')
+      pre_args += ['-D__MSVCRT_VERSION__=0x0700']
+    endif
   endif
 elif host_machine.system() == 'openbsd'
   pre_args += '-D_ISOC11_SOURCE'