intel-gpu-tools: add igt_core init func calls to some tests

igt-core.h/c provides some macros and initialisation
functions to support the tests but some of the single
tests do not use these. Modifying these tests to use
the igt_simple_main macro and igt_simple_init function
is the first step towards a consistent command line
across all tests.

Signed-off-by: Tim Gore <tim.gore@intel.com>
Signed-off-by: Thomas Wood <thomas.wood@intel.com>

tests/gem_hang.c

@@ -72,6 +72,8 @@ int main(int argc, char **argv)
 {
 	int fd;
 
+	igt_simple_init();
+
 	igt_assert_f(argc == 2,
 		     "usage: %s <disabled pipe number>\n",
 		     argv[0]);