iwlwifi: pcie: remove stray character in iwl_pcie_rx_alloc_page()

We have a solitary and inconspicous ` in the middle of a comment in
this function, which should not be there.  Remove it.
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/pcie/rx.c

@@ -434,7 +434,7 @@ static struct page *iwl_pcie_rx_alloc_page(struct iwl_trans *trans,
 		/*
 		 * Issue an error if we don't have enough pre-allocated
 		  * buffers.
-`		 */
+		 */
 		if (!(gfp_mask & __GFP_NOWARN) && net_ratelimit())
 			IWL_CRIT(trans,
 				 "Failed to alloc_pages\n");