Add Cortex-M4

[Paul Brook]

The patch below adds support for the ARM Cortex-M4. All the architecture 
support is already there, this just adds the CPU name.

Tested on arm-none-eabi.
Applied to CVS Head.

Paul

2010-03-05  Paul Brook  <paul@codesourcery.com>

	gas/
	* config/tc-arm.c (arm_cpu_option_table): Add cortex-m4.

Index: gas/config/tc-arm.c
===================================================================
--- gas/config/tc-arm.c	(revision 277588)
+++ gas/config/tc-arm.c	(working copy)
@@ -22179,6 +22179,7 @@ static const struct arm_cpu_option_table
                                                           NULL},
   {"cortex-r4",		ARM_ARCH_V7R,	 FPU_NONE,	  NULL},
   {"cortex-r4f",	ARM_ARCH_V7R,	 FPU_ARCH_VFP_V3D16,	  NULL},
+  {"cortex-m4",		ARM_ARCH_V7EM,	 FPU_NONE,	  NULL},
   {"cortex-m3",		ARM_ARCH_V7M,	 FPU_NONE,	  NULL},
   {"cortex-m1",		ARM_ARCH_V6M,	 FPU_NONE,	  NULL},
   {"cortex-m0",		ARM_ARCH_V6M,	 FPU_NONE,	  NULL},