r238211:
Support TARGET_ARCH=armv6 and TARGET_ARCH=armv6eb
This adds a new TARGET_ARCH for building on ARM
processors that support the ARMv6K multiprocessor
extensions. In particular, these processors have
better support for TLS and mutex operations.
This mostly touches a lot of Makefiles to extend
existing patterns for inferring CPUARCH from ARCH.
It also configures:
* GCC to default to arm1176jz-s
* GCC to predefine __FreeBSD_ARCH_armv6__
* gas to default to ARM_ARCH_V6K
* uname -p to return 'armv6'
* make so that MACHINE_ARCH defaults to 'armv6'
It also changes a number of headers to use
the compiler __ARM_ARCH_XXX__ macros to configure
processor-specific support routines.
Submitted by: Tim Kientzle <kientzle@freebsd.org>