target-arm/gdbstub64.c: remove useless 'break' statement.

Clean up useless 'break' statement after 'return' statement.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target-arm/gdbstub64.c

diff --git a/target-arm/gdbstub64.c b/target-arm/gdbstub64.c
index e8a8295..8f3b8d1 100644
--- a/target-arm/gdbstub64.c
+++ b/target-arm/gdbstub64.c
@@ -32,10 +32,8 @@
     switch (n) {
     case 31:
         return gdb_get_reg64(mem_buf, env->xregs[31]);
-        break;
     case 32:
         return gdb_get_reg64(mem_buf, env->pc);
-        break;
     case 33:
         return gdb_get_reg32(mem_buf, pstate_read(env));
     }