mmc: core: Fix variable shadowing in mmc_route_rpmb_frames()

Rename the inner 'frm' variable to 'resp_frm' in the write path of
mmc_route_rpmb_frames() to avoid shadowing the outer 'frm' variable.

The function declares 'frm' at function scope pointing to the request
frame, but then redeclares another 'frm' variable inside the write
block pointing to the response frame. This shadowing makes the code
confusing and error-prone.

Using 'resp_frm' for the response frame makes the distinction clear
and improves code readability.

Fixes: 7852028 ("mmc: block: register RPMB partition with the RPMB subsystem")
Reviewed-by: Avri Altman <[email protected]>
Reviewed-by: Jens Wiklander <[email protected]>
Signed-off-by: Bean Huo <[email protected]>
Signed-off-by: Ulf Hansson <[email protected]>

Author: beanhuo

drivers/mmc/core/block.c

@@ -2930,15 +2930,15 @@ static int mmc_route_rpmb_frames(struct device *dev, u8 *req,
 		return -ENOMEM;
 
 	if (write) {
-		struct rpmb_frame *frm = (struct rpmb_frame *)resp;
+		struct rpmb_frame *resp_frm = (struct rpmb_frame *)resp;
 
 		/* Send write request frame(s) */
 		set_idata(idata[0], MMC_WRITE_MULTIPLE_BLOCK,
 			  1 | MMC_CMD23_ARG_REL_WR, req, req_len);
 
 		/* Send result request frame */
-		memset(frm, 0, sizeof(*frm));
-		frm->req_resp = cpu_to_be16(RPMB_RESULT_READ);
+		memset(resp_frm, 0, sizeof(*resp_frm));
+		resp_frm->req_resp = cpu_to_be16(RPMB_RESULT_READ);
 		set_idata(idata[1], MMC_WRITE_MULTIPLE_BLOCK, 1, resp,
 			  resp_len);