sh: includecheck fix: dwarf.c

fix the following 'make includecheck' warning:

  arch/sh/kernel/dwarf.c: asm/dwarf.h is included more than once.
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/kernel/dwarf.c

@@ -24,7 +24,6 @@
 #include <asm/unwinder.h>
 #include <asm/sections.h>
 #include <asm/unaligned.h>
-#include <asm/dwarf.h>
 #include <asm/stacktrace.h>
 
 /* Reserve enough memory for two stack frames */