staging: wilc1000: fix potential memory leak

This patch adds kfree(mgmt_tx) when memory allocation of mgmt_tx->buff
fails in the second calls of kmalloc() to avoid the memory leak from mgmt_tx
first allocated before the second calls of kmalloc().

Signed-off-by: Tony Cho <tony.cho@atmel.com>
Signed-off-by: Chris Park <chirs.park@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c b/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c
index 663d0f8..cf76a33 100644
--- a/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c
+++ b/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c
@@ -2533,6 +2533,7 @@
 		mgmt_tx->buff = WILC_MALLOC(buf_len);
 		if (mgmt_tx->buff == NULL) {
 			PRINT_ER("Failed to allocate memory for mgmt_tx buff\n");
+			kfree(mgmt_tx);
 			return WILC_FAIL;
 		}
 		memcpy(mgmt_tx->buff, buf, len);