ARM: 8970/1: decompressor: increase tag size

ARM: 8970/1: decompressor: increase tag size

BugLink: https://bugs.launchpad.net/bugs/1881927
[ Upstream commit 2c962369d72f286659e6446919f88d69b943cb4d ]

The size field of the tag header structure is supposed to be set to the
size of a tag structure including the header.

Fixes: c772568788b5f0 ("ARM: add additional table to compressed kernel")
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>