Split MCAsmStreamer.
Create ARMAsmStreamer subclass.
Move eabi_attribute to MCStreamer.
Change default vendor in .ARM.attributes.
Add .eabi_attribute, .cpu, and .fpu directive to ARMAsmParser.
Enhance test cases.
Add more ARM build attributes enumeration.
Fix the incorrect .fpu directive assembler.
Cleanup FPU directive printer, parser, and assembler.
Extract common code.