Revert "[ARM] Adjust strd/ldrd codegen alignment requirements"

This reverts commit 92a9c30c.

This has caused a test failure in the 2nd stage of Linaro's
Arm 32 bit buildbots.

LLVM::simplified-template-names.s

            7: error: Simplified template DW_AT_name could not be reconstituted:
check:10'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            8:  original: f3<unsigned char, (unsigned char)'\x00'>
check:10'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            9:  reconstituted: f3<unsigned char, (unsigned char)'\x7f'>
check:10'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I suspect a load/store is slightly off.