cpuinit: get rid of __cpuinit

This commit is the result of:

find -name "*.c" | xargs sed -i "s/ __cpuinit / /g"
find -name "*.c" | xargs sed -i "s/ __cpuexit / /g"
find -name "*.c" | xargs sed -i "s/ __cpuinitdata//g"
find -name "*.c" | xargs sed -i "s/ __cpuinit$//g"
find arch/ -name "*.h" | xargs sed -i "s/ __cpuinit//g"
find -name "*.c" | xargs sed -i "s/^__cpuinit //g"