uboot-phytec

spl_fit.c: enable loading compressed u-boot from fit image

Allow reading compressed content from fit image, even if
CONFIG_SPL_OS_BOOT is not set.

This allow booting compressed 2nd stage u-boot from fit image.

Additionally, do not print warning message if compression node is not
found, since it simply implies the content is uncompressed.

Signed-off-by: Klaus H. Sorensen <khso@prevas.dk>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>