glcpp: Support #elif(expression) with no intervening space.

And add test cases to ensure that this works
	- 110 verifies that glcpp rejects #elif<digits> which glcpp
	  previously accepted.
	- 111 verifies that glcpp accepts #if followed immediately by
	  (, +, -, !, or ~.
	- 112 does the same as 111 but for #elif.

See 17f9beb6 for #if change.
Reviewed-by: Carl Worth <cworth@cworth.org>

src/glsl/glcpp/glcpp-lex.l

@@ -158,7 +158,7 @@ HEXADECIMAL_INTEGER	0[xX][0-9a-fA-F]+[uU]?
 	return HASH_IF;
 }
 
-{HASH}elif {
+{HASH}elif/[^_a-zA-Z0-9] {
 	yyextra->lexing_if = 1;
 	yyextra->space_tokens = 0;
 	return HASH_ELIF;

src/glsl/glcpp/tests/110-no-space-digits-after-hash-elif.c

@@ -0,0 +1,3 @@
+#if 1
+#elif110
+#endif

src/glsl/glcpp/tests/110-no-space-digits-after-hash-elif.c.expected

@@ -0,0 +1,4 @@
+0:2(2): preprocessor error: Invalid tokens after #
+
+
+

src/glsl/glcpp/tests/111-no-space-operator-after-hash-if.c

@@ -0,0 +1,19 @@
+#if(1)
+success
+#endif
+
+#if+1
+success
+#endif
+
+#if-1
+success
+#endif
+
+#if!1
+success
+#endif
+
+#if~1
+success
+#endif

src/glsl/glcpp/tests/111-no-space-operator-after-hash-if.c.expected

@@ -0,0 +1,20 @@
+
+success
+
+
+
+success
+
+
+
+success
+
+
+
+
+
+
+
+success
+
+

src/glsl/glcpp/tests/112-no-space-operator-after-hash-elif.c

@@ -0,0 +1,24 @@
+#if 0
+#elif(1)
+success
+#endif
+
+#if 0
+#elif+1
+success
+#endif
+
+#if 0
+#elif-1
+success
+#endif
+
+#if 0
+#elif!1
+success
+#endif
+
+#if 0
+#elif~1
+success
+#endif

src/glsl/glcpp/tests/112-no-space-operator-after-hash-elif.c.expected

@@ -0,0 +1,25 @@
+
+
+success
+
+
+
+
+success
+
+
+
+
+success
+
+
+
+
+
+
+
+
+
+success
+
+