bts: define egprs_enabled as bool

Change-Id: I66a8254ee392ad75226c58b7df5746f409463f0f
diff --git a/src/pcu_vty.c b/src/pcu_vty.c
index 1602aef..6dfcdf5 100644
--- a/src/pcu_vty.c
+++ b/src/pcu_vty.c
@@ -281,7 +281,7 @@
 {
 	struct gprs_rlcmac_bts *bts = bts_main_data();
 
-	bts->egprs_enabled = 1;
+	bts->egprs_enabled = true;
 
 	return CMD_SUCCESS;
 }
@@ -294,7 +294,7 @@
 {
 	struct gprs_rlcmac_bts *bts = bts_main_data();
 
-	bts->egprs_enabled = 0;
+	bts->egprs_enabled = false;
 
 	return CMD_SUCCESS;
 }