gbproxy: Fix warnings

This patch fixes the remaining 'unused' warnings.

Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy.c b/openbsc/src/gprs/gb_proxy.c
index 965059b..a61a307 100644
--- a/openbsc/src/gprs/gb_proxy.c
+++ b/openbsc/src/gprs/gb_proxy.c
@@ -116,7 +116,6 @@
 	const uint8_t e_bit = 0;
 	const uint8_t pm_bit = 1;
 	const uint8_t cr_bit = is_uplink ? 0 : 1;
-	size_t msg_size = msgb_length(msg);
 	uint8_t *llc;
 	uint8_t *fcs_field;
 	uint32_t fcs;
diff --git a/openbsc/src/gprs/gprs_gb_parse.c b/openbsc/src/gprs/gprs_gb_parse.c
index ef4a4d1..fe08817 100644
--- a/openbsc/src/gprs/gprs_gb_parse.c
+++ b/openbsc/src/gprs/gprs_gb_parse.c
@@ -224,7 +224,6 @@
 {
 	uint8_t *value;
 	size_t value_len;
-	int detach_type;
 	int power_off;
 
 	parse_ctx->llc_msg_name = "DETACH_REQ";
@@ -235,7 +234,6 @@
 		/* invalid */
 		return 0;
 
-	detach_type = *value & 0x07;
 	power_off = *value & 0x08 ? 1 : 0;
 
 	if (!parse_ctx->to_bss) {