asm build warnings w/ cross-compiler about IT block deprecation for ARMv8

We should either suppress these or decide we don't need to test these corner cases (probably former is better):

/work/dr/git/src/suite/tests/common/allasm_thumb.asm: Assembler messages: /work/dr/git/src/suite/tests/common/allasm_thumb.asm:105: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:105: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:110: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:116: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:122: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:128: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:148: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:150: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:166: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:166: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:171: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:188: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:193: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:202: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:208: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:215: Warning: it blocks containing 16-bit Thumb intsructions of the following class are deprecated in ARMv8: Literal loads /work/dr/git/src/suite/tests/common/allasm_thumb.asm:229: Warning: it blocks containing wide Thumb instructions are deprecated in ARMv8 /work/dr/git/src/suite/tests/common/allasm_thumb.asm:254: Warning: it blocks of more than one conditional instruction are deprecated in ARMv8