Revert "efi_loader: efi_allocate_pages is too restrictive"

This reverts commit aa909462d01866354f4cd4534db5f571c2cf1fbb. This change
caused "dhcp filename" to crash the system on p2371-2180 (Jetson TX1), for
example when running test/py.

Reverting this change isn't optimal, but at least restores TX1 to a working
state. In the future, we should:

a) Fix whatever problem causes the crash with this patch applied. This
needs further discussion, so isn't something we can immediately do.

b) Undo the revert; re-apply the original patch to efi_allocate_pages.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

lib/efi_loader/efi_memory.c

@@ -305,7 +305,7 @@ efi_status_t efi_allocate_pages(int type, int memory_type,
 	switch (type) {
 	case EFI_ALLOCATE_ANY_PAGES:
 		/* Any page */
-		addr = efi_find_free_memory(len, -1ULL);
+		addr = efi_find_free_memory(len, gd->start_addr_sp);
 		if (!addr) {
 			r = EFI_NOT_FOUND;
 			break;