gdbstub: drop CPUEnv from gdb_exit()

gdb_exit() has never needed anything from env and I doubt we are going
to start now.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210108224256.2321-8-alex.bennee@linaro.org>
diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c
index f7b7bff..93360e2 100644
--- a/target/arm/arm-semi.c
+++ b/target/arm/arm-semi.c
@@ -1101,7 +1101,7 @@
              */
             ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
         }
-        gdb_exit(env, ret);
+        gdb_exit(ret);
         exit(ret);
     case TARGET_SYS_SYNCCACHE:
         /*