OpenMP: Add omp_get_initial_device/omp_get_num_devices builtins: Fix test cases

OpenMP: Add omp_get_initial_device/omp_get_num_devices builtins: Fix test cases

With this fix-up for commit 387209938d2c476a67966c6ddbdbf817626f24a2
"OpenMP: Add omp_get_initial_device/omp_get_num_devices builtins", we progress:

     PASS: c-c++-common/gomp/omp_get_num_devices_initial_device.c (test for excess errors)
     PASS: c-c++-common/gomp/omp_get_num_devices_initial_device.c scan-tree-dump-not optimized "abort"
    -FAIL: c-c++-common/gomp/omp_get_num_devices_initial_device.c scan-tree-dump-times optimized "omp_get_num_devices;" 1
    +PASS: c-c++-common/gomp/omp_get_num_devices_initial_device.c scan-tree-dump-times optimized "omp_get_num_devices" 1
     PASS: c-c++-common/gomp/omp_get_num_devices_initial_device.c scan-tree-dump optimized "_1 = __builtin_omp_get_num_devices \\(\\);[\\r\\n]+[ ]+return _1;"

... etc. for offloading configurations.

	gcc/testsuite/
	* c-c++-common/gomp/omp_get_num_devices_initial_device.c: Fix.
	* gfortran.dg/gomp/omp_get_num_devices_initial_device.f90: Likewise.

(cherry picked from commit 13c766066e23eb6ddf6bad7a5664b9d3ca8c1974)