intel: protect against empty invalidate ranges

It's legal for an application to call vkInvalidateMappedMemoryRanges()
/ vkFlushMappedMemoryRanges() with zero sized ranges.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Fixes: b91971c240 ("anv: use the right helper to invalidate memory")
Cc: mesa-stable
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/6852
Reviewed-by: Marcin Ślusarz <marcin.slusarz@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17481>

src/intel/common/intel_clflush.h

@@ -49,6 +49,9 @@ intel_flush_range(void *start, size_t size)
 static inline void
 intel_invalidate_range(void *start, size_t size)
 {
+   if (size == 0)
+      return;
+
    intel_clflush_range(start, size);
 
    /* Modern Atom CPUs (Baytrail+) have issues with clflush serialization,