mmc_block: hard code 512 byte block size
mmc_block: hard code 512 byte block size

We use 512 byte blocks on all cards, and newer cards support nothing
else, so hard code it and make the code less complex.

Signed-off-by: Pierre Ossman <8b64f2aeec7ea42cd6838e5b2901f7aa61dfa5d4@drzeus.cx>

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