[SPARC]: Fix link errors with gcc-4.3

Reported by Adrian Bunk.

Just like in changeset a3f99858
("[SPARC64]: Move kernel unaligned trap handlers into assembler
file.") we have to move the assembler bits into a seperate
asm file because as far as the compiler is concerned
these inline bits we're doing in unaligned.c are unreachable.

Signed-off-by: David S. Miller <davem@davemloft.net>