libcpp: Diagnose __has_include outside of preprocessor directives [PR93545]

Add forgotten gcc/testsuite/c-c++-common/gomp/has-include-1.c.

2020-02-04  Jakub Jelinek  <jakub@redhat.com>

	* macro.c (builtin_has_include): Diagnose __has_include* use outside
	of preprocessing directives.

	* c-c++-common/cpp/has-include-1.c: New test.
	* c-c++-common/cpp/has-include-next-1.c: New test.
	* c-c++-common/gomp/has-include-1.c: New test.

gcc/testsuite/c-c++-common/gomp/has-include-1.c

+/* { dg-do compile } */
+
+void
+foo (void)
+{
+#pragma omp parallel if (__has_include ("<stdlib.h>"))	/* { dg-error "used outside of preprocessing directive" } */
+  ;
+}