bug.h: add include of it to various implicit C users

With bug.h currently living right in linux/kernel.h there
are files that use BUG_ON and friends but are not including
the header explicitly.  Fix them up so we can remove the
presence in kernel.h file.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/arch/parisc/math-emu/fpudispatch.c b/arch/parisc/math-emu/fpudispatch.c
index 6e28f9f..673b73e 100644
--- a/arch/parisc/math-emu/fpudispatch.c
+++ b/arch/parisc/math-emu/fpudispatch.c
@@ -50,6 +50,7 @@
 #define FPUDEBUG 0
 
 #include "float.h"
+#include <linux/bug.h>
 #include <linux/kernel.h>
 #include <asm/processor.h>
 /* #include <sys/debug.h> */