boot: Drop unnecessary assignment in bootm_find_images()

Since 'select' is already assigned in the declarations for this
function, there is no need to do it again. Drop the duplicate
assignment.

Signed-off-by: Simon Glass <sjg@chromium.org>

boot/bootm.c

@@ -531,9 +531,6 @@ int bootm_find_images(ulong img_addr, const char *conf_ramdisk,
 		}
 	}
 
-	if (conf_ramdisk)
-		select = conf_ramdisk;
-
 	/* find ramdisk */
 	ret = boot_get_ramdisk(select, &images, IH_INITRD_ARCH,
 			       &images.rd_start, &images.rd_end);