fastboot: getvar: fix partition-size return value

The size returned by 'getvar partition-size' should be in bytes, not in
blocks as fastboot uses that value to generate empty partition when
running format [1].

Note that the function was already returning the proper size in bytes
for NAND devices (see struct part_info details).

[1]
https://android.googlesource.com/platform/system/core/+/refs/heads/android10-release/fastboot/fastboot.cpp#1500

Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
diff --git a/drivers/fastboot/fb_getvar.c b/drivers/fastboot/fb_getvar.c
index 52da34b..d43f2cf 100644
--- a/drivers/fastboot/fb_getvar.c
+++ b/drivers/fastboot/fb_getvar.c
@@ -95,7 +95,7 @@
  *
  * @param[in] part_name Info for which partition name to look for
  * @param[in,out] response Pointer to fastboot response buffer
- * @param[out] size If not NULL, will contain partition size (in blocks)
+ * @param[out] size If not NULL, will contain partition size
  * @return Partition number or negative value on error
  */
 static int getvar_get_part_info(const char *part_name, char *response,
@@ -109,7 +109,7 @@
 	r = fastboot_mmc_get_part_info(part_name, &dev_desc, &part_info,
 				       response);
 	if (r >= 0 && size)
-		*size = part_info.size;
+		*size = part_info.size * part_info.blksz;
 # elif CONFIG_IS_ENABLED(FASTBOOT_FLASH_NAND)
 	struct part_info *part_info;