riscv: mm: use bitmap_zero() API

bitmap_zero() is faster than bitmap_clear(), so use bitmap_zero()
instead of bitmap_clear().

Signed-off-by: Ye Xingchen <ye.xingchen@zte.com.cn>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/202305061711417142802@zte.com.cn
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/mm/context.c

@@ -67,7 +67,7 @@ static void __flush_context(void)
 	lockdep_assert_held(&context_lock);
 
 	/* Update the list of reserved ASIDs and the ASID bitmap. */
-	bitmap_clear(context_asid_map, 0, num_asids);
+	bitmap_zero(context_asid_map, num_asids);
 
 	/* Mark already active ASIDs as used */
 	for_each_possible_cpu(i) {