Mark extern variables with 'extern' keyword

This ensures that compilers with -fno-common does not generate multiple definitions

Upstream-Status: Pending
Signedd-off-by: Khem Raj <raj.khem@gmail.com>

--- a/lib/wfa_cs.c
+++ b/lib/wfa_cs.c
@@ -71,7 +71,7 @@ int wfaExecuteCLI(char *CLI);
 
 /* Since the two definitions are used all over the CA function */
 char gCmdStr[WFA_CMD_STR_SZ];
-dutCmdResponse_t gGenericResp;
+extern dutCmdResponse_t gGenericResp;
 int wfaTGSetPrio(int sockfd, int tgClass);
 void create_apts_msg(int msg, unsigned int txbuf[],int id);
 
--- a/lib/wfa_thr.c
+++ b/lib/wfa_thr.c
@@ -41,7 +41,7 @@
 /*
  * external global thread sync variables
  */
-tgWMM_t wmm_thr[WFA_THREADS_NUM];
+extern tgWMM_t wmm_thr[WFA_THREADS_NUM];
 extern int resetsnd;
 extern int resetrcv;
 extern int newCmdOn;