spl: Only support bl_len when we have to

Aligning addresses and sizes causes overhead which is unnecessary when we
are not loading from block devices. Remove bl_len when it is not needed.

For example, on iot2050 we save 144 bytes with this patch (once the rest of
this series is applied):

add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-144 (-144)
Function                                     old     new   delta
spl_load_simple_fit                          920     904     -16
load_simple_fit                              496     444     -52
spl_spi_load_image                           384     308     -76
Total: Before=87431, After=87287, chg -0.16%

We use panic() instead of BUILD_BUG_ON in spl_set_bl_len because we still
need to be able to compile it for things like mmc_load_image_raw_sector,
even if that function will not be used.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/spl/spl_imx_container.c b/common/spl/spl_imx_container.c
index 7cd674f..b4ea924 100644
--- a/common/spl/spl_imx_container.c
+++ b/common/spl/spl_imx_container.c
@@ -32,13 +32,13 @@
 	images = (struct boot_img_t *)((u8 *)container +
 				       sizeof(struct container_hdr));
 
-	if (!IS_ALIGNED(images[image_index].offset, info->bl_len)) {
+	if (!IS_ALIGNED(images[image_index].offset, spl_get_bl_len(info))) {
 		printf("%s: image%d offset not aligned to %u\n",
-		       __func__, image_index, info->bl_len);
+		       __func__, image_index, spl_get_bl_len(info));
 		return NULL;
 	}
 
-	size = ALIGN(images[image_index].size, info->bl_len);
+	size = ALIGN(images[image_index].size, spl_get_bl_len(info));
 	offset = images[image_index].offset + container_offset;
 
 	debug("%s: container: %p offset: %lu size: %lu\n", __func__,
@@ -66,7 +66,7 @@
 	u16 length;
 	int i, size, ret = 0;
 
-	size = ALIGN(CONTAINER_HDR_ALIGNMENT, info->bl_len);
+	size = ALIGN(CONTAINER_HDR_ALIGNMENT, spl_get_bl_len(info));
 
 	/*
 	 * It will not override the ATF code, so safe to use it here,
@@ -100,7 +100,7 @@
 	debug("Container length %u\n", length);
 
 	if (length > CONTAINER_HDR_ALIGNMENT) {
-		size = ALIGN(length, info->bl_len);
+		size = ALIGN(length, spl_get_bl_len(info));
 
 		free(container);
 		container = malloc(size);