spi: mxic: add missing braces

Fix the following waring:

drivers/spi/spi-mxic.c: In function ‘mxic_spi_mem_exec_op’:
drivers/spi/spi-mxic.c:401:3: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
   if (op->data.dir == SPI_MEM_DATA_IN)
   ^~
drivers/spi/spi-mxic.c:403:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
    if (op->data.dtr)
    ^~
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Zhengxun Li <zhengxunli@mxic.com.tw>
Link: https://lore.kernel.org/r/20210810142405.2221540-1-yangyingliang@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-mxic.c

@@ -398,10 +398,11 @@ static int mxic_spi_mem_exec_op(struct spi_mem *mem,
 	if (op->data.nbytes) {
 		ss_ctrl |= OP_DATA_BUSW(fls(op->data.buswidth) - 1) |
 			   (op->data.dtr ? OP_DATA_DDR : 0);
-		if (op->data.dir == SPI_MEM_DATA_IN)
+		if (op->data.dir == SPI_MEM_DATA_IN) {
 			ss_ctrl |= OP_READ;
 			if (op->data.dtr)
 				ss_ctrl |= OP_DQS_EN;
+		}
 	}
 
 	writel(ss_ctrl, mxic->regs + SS_CTRL(mem->spi->chip_select));