bnxt: Use the bitmap API to allocate bitmaps

Use bitmap_zalloc()/bitmap_free() instead of hand-writing them.

It is less verbose and it improves the semantic.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/d508f3adf7e2804f4d3793271b82b196a2ccb940.1657052562.git.christophe.jaillet@wanadoo.frSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -4477,7 +4477,7 @@ static void bnxt_free_ntp_fltrs(struct bnxt *bp, bool irq_reinit)
 		}
 	}
 	if (irq_reinit) {
-		kfree(bp->ntp_fltr_bmap);
+		bitmap_free(bp->ntp_fltr_bmap);
 		bp->ntp_fltr_bmap = NULL;
 	}
 	bp->ntp_fltr_count = 0;
@@ -4496,9 +4496,7 @@ static int bnxt_alloc_ntp_fltrs(struct bnxt *bp)
 		INIT_HLIST_HEAD(&bp->ntp_fltr_hash_tbl[i]);
 
 	bp->ntp_fltr_count = 0;
-	bp->ntp_fltr_bmap = kcalloc(BITS_TO_LONGS(BNXT_NTP_FLTR_MAX_FLTR),
-				    sizeof(long),
-				    GFP_KERNEL);
+	bp->ntp_fltr_bmap = bitmap_zalloc(BNXT_NTP_FLTR_MAX_FLTR, GFP_KERNEL);
 
 	if (!bp->ntp_fltr_bmap)
 		rc = -ENOMEM;