powerpc: Fix define_machine so machine_is() works from modules
powerpc: Fix define_machine so machine_is() works from modules

machine_is() was always returning 0 when used in a module, because
we weren't exporting the machine definitions.  This was why sound
wasn't working on powermacs when CONFIG_SND_POWERMAC=m.  Original
fix from Ben Herrenschmidt, further fixed by me.

Signed-off-by: Paul Mackerras <19a0ba370c443ba08d20b5061586430ab449ee8c@samba.org>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs