Revert "lmb: Default to not-LMB_USE_MAX_REGIONS"

As explained by Philippe Schenker, I was misinterpreting what happened
in the case where we do not set LMB_USE_MAX_REGIONS and so had
re-introduced the problem I was attempting to more widely resolve.

This reverts commit 007ae5d108a37564905ea1588cb279f3a522cc3d.

Reported-by: Philippe Schenker <philippe.schenker@toradex.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/mt7981_sd_rfb_defconfig b/configs/mt7981_sd_rfb_defconfig
index 17592dc..85be9bb 100644
--- a/configs/mt7981_sd_rfb_defconfig
+++ b/configs/mt7981_sd_rfb_defconfig
@@ -62,3 +62,4 @@
 CONFIG_FAT_WRITE=y
 CONFIG_HEXDUMP=y
 # CONFIG_EFI_LOADER is not set
+CONFIG_LMB_MAX_REGIONS=64