Fix test failure in openSUSE 15.5

The #include <bits/floatn.h> is not available in the system thus can't
be safely checked.

Signed-off-by: Giuliano Belinassi <gbelinassi@suse.de>

testsuite/includes/include-7.c

@@ -18,5 +18,4 @@ int main(void)
 /* { dg-final { scan-tree-dump "#include <bits/types/struct_FILE.h>" } } */
 /* { dg-final { scan-tree-dump "#include <bits/stdio_lim.h>" } } */
 /* { dg-final { scan-tree-dump "extern int printf \(const char \*__restrict __format, ...\);" } } */
-/* { dg-final { scan-tree-dump "#include <bits/floatn.h>" } } */
 /* { dg-final { scan-tree-dump "int main\(void\)" } } */