ARM: 7508/1: opcodes: Don't define the thumb32 byteswapping macros for BE32

The existing __mem_to_opcode_thumb32() is incorrect for BE32
platforms.  However, these don't support Thumb-2 kernels, so this
option is not so relevant for those platforms anyway.

This operation is complicated by the lack of unaligned memory
access support prior to ARMv6.

Rather than provide a "working" macro which will probably won't get
used (or worse, will get misused), this patch removes the macro for
BE32 kernels.  People manipulating Thumb opcodes prior to ARMv6
should almost certainly be splitting these operations into
halfwords anyway, using __opcode_thumb32_{first,second,compose}()
and the 16-bit opcode transformations.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>