* arm/arm.h: (CPP_SPEC): Define __ARMEB__, __ARMEL__, and
	__ARMWEL__ depending on the endian flags passed to the compiler.
	(ARM_FLAG_LITTLE_WORDS): Define.
	(TARGET_SWITCHES): Add option -mwords-little-endian.
	(TARGET_LITTLE_WORDS): Define.
	(WORDS_BIG_ENDIAN): Select based on the endian switches.
	(LIBGCC2_WORDS_BIG_ENDIAN): Define based on run-time endian
	defines.

From-SVN: r11211