[clang] Fix test to require x86

This test would fail if the x86 target had not been built. This fix
makes the requirement on x86 explicit. Trailing whitespace has also been
removed.

Author: tarunprabhu

clang/test/OpenMP/nvptx_throw_trap.cpp

@@ -1,4 +1,4 @@
-// REQUIRES: nvptx-registered-target
+// REQUIRES: nvptx-registered-target, x86-registered-target
 
 // RUN: %clang_cc1 -fopenmp -triple nvptx64 -fopenmp-is-target-device %s -S -Wno-openmp-target-exception -o - | FileCheck -check-prefix=DEVICE %s
 // RUN: %clang_cc1 -fopenmp -triple x86_64-pc-linux-gnu -fopenmp-is-target-device -fcxx-exceptions %s -S -Wno-openmp-target-exception -o - | FileCheck -check-prefix=HOST %s
@@ -8,6 +8,6 @@
 // HOST-NOT: trap;
 #pragma omp declare target
 void foo(void) {
-	throw 404; 
+	throw 404;
 }
 #pragma omp end declare target