Added support for ARMV8-M Security Extension cmse_nonsecure_caller intrinsic

Added support for ARMV8-M Security Extension cmse_nonsecure_caller intrinsic

    gcc/ChangeLog:
    2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
		Thomas Preud'homme  <thomas.preudhomme@arm.com>

	* config/arm/arm-builtins.c (arm_builtins): Define
	ARM_BUILTIN_CMSE_NONSECURE_CALLER.
	(bdesc_2arg): Add line for cmse_nonsecure_caller.
	(arm_init_builtins): Handle cmse_nonsecure_caller.
	(arm_expand_builtin): Likewise.
	* config/arm/arm_cmse.h (cmse_nonsecure_caller): New.

    gcc/testsuite/ChangeLog:
    2016-12-02  Andre Vieira  <andre.simoesdiasvieira@arm.com>
		Thomas Preud'homme  <thomas.preudhomme@arm.com>

	* gcc.target/arm/cmse/cmse-1.c: Add test for
	cmse_nonsecure_caller.

Co-Authored-By: Thomas Preud'homme <thomas.preudhomme@arm.com>
From-SVN: r243193