mips: unhide uasm_in_compat_space_p() declaration

uasm_in_compat_space_p() has a conditional declaration but is defined
unconditionally because of another local user, which causes a warning:

arch/mips/mm/uasm.c:421:5: error: no previous prototype for 'uasm_in_compat_space_p' [-Werror=missing-prototypes]

Make the declaration unconditional to avoid this.

Link: https://lkml.kernel.org/r/20231204115710.2247097-10-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>