xtensa: fix build error in xtensa/include/asm/io.h
xtensa: fix build error in xtensa/include/asm/io.h

Caused by commit 6c03438edeb5c359af35f060ea016ca65671c269

    kernel.h: doesn't explicitly use bug.h, so don't include it.

This header uses bug.h so explicitly include it now that the
implicit presence was removed by 6c03438ed.

Signed-off-by: Paul Gortmaker <ae947f3c8df96e1dc851c5e3e5a930ce6d3f1f74@windriver.com>

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