Remove inline qualifier from show_boot_progress()

The 'inline' is conflicting with the semantic of 'weak' attribute and with the
way the show_boot_progress() function is used.

Also gcc 4.4 is complaining about it:

main.c:51: error: inline function 'show_boot_progress' cannot be declared weak

Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>