tests/tcg/hexagon: fix underspecifed asm constraints

tests/tcg/hexagon: fix underspecifed asm constraints

There are two test cases where the inline asm doesn't
have the correct constraints causing them to fail.

In misc.c, the 'result' output needs the early clobber
modifier since the rest of the inputs are read after
assignment to the output register.

In mem_noshuf.c, the register r7 is written to but
not specified in the clobber list.

Signed-off-by: Mukilan Thiyagarajan <quic_mthiyaga@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221229081836.12130-1-quic_mthiyaga@quicinc.com>