[ARM] Rework expectation for call to Armv8-M nonsecure function

Testcase gcc.target/arm/cmse/cmse-14.c checks whether bar is called via
__gnu_cmse_nonsecure_call libcall and not via a direct call. However the
pattern is a bit surprising in that it needs to explicitely allow "by"
due to allowing anything before the 'b'.

This patch rewrites the logic to look for b as a first non-whitespace
letter followed iby anything (to match bl and conditional branches)
followed by some spaces and then bar.

2017-11-17  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/testsuite/
    * gcc.target/arm/cmse/cmse-14.c: Change logic to match branch
    instruction to bar.

From-SVN: r254861

gcc/testsuite/ChangeLog

 2017-11-17  Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
+	* gcc.target/arm/cmse/cmse-14.c: Change logic to match branch
+	instruction to bar.
+
+2017-11-17  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
 	* gcc.target/arm/cmse/cmse.exp: Add option to select Armv8-M Baseline
 	or Armv8-M Mainline when running the respective tests.
 	* gcc.target/arm/cmse/baseline/cmse-11.c: Remove architecture check and

gcc/testsuite/gcc.target/arm/cmse/cmse-14.c

@@ -10,4 +10,4 @@ int foo (void)
 }
 
 /* { dg-final { scan-assembler "bl\t__gnu_cmse_nonsecure_call" } } */
-/* { dg-final { scan-assembler-not "b\[^ y\n\]*\\s+bar" } } */
+/* { dg-final { scan-assembler-not "^(.*\\s)?bl?\[^\\s]*\\s+bar" } } */