-mno-long-calls for arm/no_unique_address tests

-mno-long-calls for arm/no_unique_address tests

The implicit -mlong-calls from our vxworks configurations makes the
tail-call instructions differ from those expected by the
no_unique_address tests in gcc.target/arm.

This patch adds -mno-long-calls to the compilation commands, so that
we generate the expected sequences.

for  gcc/testsuite/ChangeLog

	* g++.target/arm/no_unique_address_1.C: Add -mno-long-calls.
	* g++.target/arm/no_unique_address_2.C: Likewise.