microblaze: Remove old user debugging gdb stub

Old gdb uses priviledged exception handler to handle
gdb exception. New gdb uses brki r16, 0x18 that's why
we can remove old gdb support.
Signed-off-by: Michal Simek <monstr@monstr.eu>

arch/microblaze/kernel/exceptions.c

@@ -72,7 +72,6 @@ asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
 							int fsr, int addr)
 {
 #ifdef CONFIG_MMU
-	int code;
 	addr = regs->pc;
 #endif
 
@@ -144,13 +143,7 @@ asmlinkage void full_exception(struct pt_regs *regs, unsigned int type,
 #ifdef CONFIG_MMU
 	case MICROBLAZE_PRIVILEGED_EXCEPTION:
 		pr_debug("Privileged exception\n");
-		/* "brk r0,r0" - used as debug breakpoint - old toolchain */
-		if (get_user(code, (unsigned long *)regs->pc) == 0
-			&& code == 0x980c0000) {
-			_exception(SIGTRAP, regs, TRAP_BRKPT, addr);
-		} else {
-			_exception(SIGILL, regs, ILL_PRVOPC, addr);
-		}
+		_exception(SIGILL, regs, ILL_PRVOPC, addr);
 		break;
 #endif
 	default: