arm: Increase zImage length after getting the tag

Increase the size of the zImage after seeking for the tag to avoid
reading past the end of the supplied buffer should there be not tag
in the zImage.

Fixes: f57f0bf8975d24fe1e7c4936fdfb5c3b123ab75f
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Cc: Russell King <rmk@armlinux.org.uk>
Signed-off-by: Simon Horman <horms@verge.net.au>
1 file changed