powerpc: No need to initialise statics to 0

Static variables do not need to be initialised to 0, because compiler
will initialise all uninitialised statics to 0. Thus, remove the
unneeded initializations.

Signed-off-by: Xiang wangx <wangxiang@cdjrlc.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211221033423.29820-1-wangxiang@cdjrlc.com