sim: microblaze: replace custom basic types with common ones

sim: microblaze: replace custom basic types with common ones

The basic "byte" type conflicts with Windows headers, and we already
have common types that provide the right sizes.  So replace these with
the common ones to avoid issues.

  CC     dv-sockser.o
In file included from /usr/i686-w64-mingw32/usr/include/wtypes.h:8,
                 from /usr/i686-w64-mingw32/usr/include/winscard.h:10,
                 from /usr/i686-w64-mingw32/usr/include/windows.h:97,
                 from /usr/i686-w64-mingw32/usr/include/winsock2.h:23,
                 from ../../gnulib/import/sys/socket.h:684,
                 from ../../gnulib/import/netinet/in.h:43,
                 from .../build/sim/../../../sim/microblaze/../common/dv-sockser.c:39:
/usr/i686-w64-mingw32/usr/include/rpcndr.h:63:25: error: conflicting types for 'byte'; have 'unsigned char'
   63 |   typedef unsigned char byte;
      |                         ^~~~
In file included from .../buildsim/../../../sim/microblaze/sim-main.h:21,
                 from .../buildsim/../../../sim/microblaze/../common/dv-sockser.c:24:
.../buildsim/../../../sim/microblaze/microblaze.h:94:25: note: previous declaration of 'byte' with type 'byte' {aka 'char'}
   94 | typedef char            byte;
      |                         ^~~~
make: *** [Makefile:513: dv-sockser.o] Error 1