target-ppc: Fix target_disas

Inspect only bit 16 for the Little Endian test.  Correct comment preceding
the target_disas() function.  Correct grammar in comment for flags processing.

Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
monitor: QEMU Monitor Instruction Disassembly Incorrect for PowerPC LE Mode

The monitor support for disassembling instructions does not honor the MSR[LE]
bit for PowerPC processors.

This change enhances the monitor_disas() routine by supporting a flag bit
for Little Endian mode.  Bit 16 is used since that bit was used in the
analagous guest disassembly routine target_disas().

Also, to be consistent with target_disas(), the disassembler bfd_mach field
can be passed in the flags argument.

Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alexander Graf <agraf@suse.de>