uboot-imx

SPL ext: cosmetic: correct error message in spl_load_image_ext()

Correct the error message in spl_load_image_ext() when image parsing
fails. Instead of "ext4fs_read failed" print "failed to parse image
header".

Signed-off-by: Petr Kulhavy <brain@jikos.cz>
CC: Guillaume GARDET <guillaume.gardet@free.fr>
CC: Tom Rini <trini@konsulko.com>