Add RenderScript ArchType

Summary:
Add renderscript32 and renderscript64 ArchTypes.  This is to configure
the ABI requirement on 32-bit RenderScript that 'long' types have 64-bit
size and alignment.  64-bit RenderScript is the same as AArch64, but is
added here for completeness.

Reviewers: echristo, rsmith

Subscribers: aemerson, jfb, rampitec, dschuff, mehdi_amini, llvm-commits, srhines

Differential Revision: http://reviews.llvm.org/D21333

llvm-svn: 274412