Add newline at the end of file to fix test failure (#627)

The lit tests under test/multilib must have a newline at the end of the
file so that FileCheck checks with "-EMPTY" work correctly.

Author: vhscampos

test/multilib/armv6m.test

@@ -22,4 +22,4 @@
 # RUN: %clang -print-multi-directory --target=armv6m-none-eabi -mbig-endian -mfpu=none | FileCheck %s --check-prefix=CHECK-BE-NOFP-EXN-RTTI
 # RUN: %clang -print-multi-directory --target=armv6m-none-eabi -mbig-endian -mfpu=none -mno-unaligned-access | FileCheck %s --check-prefix=CHECK-BE-NOFP-EXN-RTTI
 # CHECK-BE-NOFP-EXN-RTTI: arm-none-eabi/armebv6m_soft_nofp_exn_rtti{{$}}
-# CHECK-BE-NOFP-EXN-RTTI-EMPTY:
+# CHECK-BE-NOFP-EXN-RTTI-EMPTY: