ipack: add error handling for ioremap_nocache

When ioremap_nocache fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling ioremap_nocache.

Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Acked-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>