linux-user: Add translation for argument of msync()

msync() uses the flags MS_ASYNC, MS_INVALIDATE and MS_SYNC, which differ
between platforms, specifcally on alpha and hppa.

Add a target to host translation for those and wire up a nicer strace
output.

This fixes the testsuite of the macaulay2 debian package with a hppa-linux
guest on a x86-64 host.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>

Message-Id: <Y5rMcts4qe15RaVN@p100>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>