sandbox: Correct compiler warnings in cmd_bootm/cmd_ximg

Correct the following warnings found with sandbox when compression
is enabled.

cmd_bootm.c: In function 'bootm_load_os':
cmd_bootm.c:443:11: warning: passing argument 4 of 'lzop_decompress' from incompatible pointer type [enabled by default]
/usr/local/google/c/cosarm/src/third_party/u-boot/files/include/linux/lzo.h:31:5: note: expected 'size_t *' but argument is of type 'uint *'
cmd_ximg.c: In function 'do_imgextract':
cmd_ximg.c:225:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
cmd_ximg.c:225:14: warning: 'hdr' may be used uninitialized in this function [-Wuninitialized]

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
diff --git a/common/cmd_bootm.c b/common/cmd_bootm.c
index 1685c14..2dd2642 100644
--- a/common/cmd_bootm.c
+++ b/common/cmd_bootm.c
@@ -436,11 +436,12 @@
 	}
 #endif /* CONFIG_LZMA */
 #ifdef CONFIG_LZO
-	case IH_COMP_LZO:
+	case IH_COMP_LZO: {
+		size_t size;
+
 		printf("   Uncompressing %s ... ", type_name);
 
-		ret = lzop_decompress(image_buf, image_len, load_buf,
-				      &unc_len);
+		ret = lzop_decompress(image_buf, image_len, load_buf, &size);
 		if (ret != LZO_E_OK) {
 			printf("LZO: uncompress or overwrite error %d "
 			      "- must RESET board to recover\n", ret);
@@ -449,8 +450,9 @@
 			return BOOTM_ERR_RESET;
 		}
 
-		*load_end = load + unc_len;
+		*load_end = load + size;
 		break;
+	}
 #endif /* CONFIG_LZO */
 	default:
 		printf("Unimplemented compression type %d\n", comp);