microblaze: kgdb: Remove unused variable and fix return value

I forget to remove unused variable from kgdb_arch_handle_exception.
Fix return value in microblaze_kgdb_break function.

Error log:
arch/microblaze/kernel/kgdb.c: In function 'microblaze_kgdb_break':
arch/microblaze/kernel/kgdb.c:83: warning: 'return' with a value, in function returning void
arch/microblaze/kernel/kgdb.c: In function 'kgdb_arch_handle_exception':
arch/microblaze/kernel/kgdb.c:119: warning: unused variable 'cpu'
Signed-off-by: NMichal Simek <monstr@monstr.eu>

arch/microblaze/kernel/kgdb.c

@@ -80,7 +80,7 @@ void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
 void microblaze_kgdb_break(struct pt_regs *regs)
 {
 	if (kgdb_handle_exception(1, SIGTRAP, 0, regs) != 0)
-		return 0;
+		return;
 
 	/* Jump over the first arch_kgdb_breakpoint which is barrier to
 	 * get kgdb work. The same solution is used for powerpc */
@@ -114,7 +114,6 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
 {
 	char *ptr;
 	unsigned long address;
-	int cpu = smp_processor_id();
 
 	switch (remcom_in_buffer[0]) {
 	case 'c':