ARM: 6893/1: Allow for kernel command line concatenation

ARM: 6893/1: Allow for kernel command line concatenation

This patch allows the provided CONFIG_CMDLINE to be concatenated
with the one provided by the boot loader. This is useful to
merge the static values defined in CONFIG_CMDLINE with the
boot loader's (possibly) more dynamic values, such as startup
reasons and more.

Signed-off-by: Victor Boivie <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Signed-off-by: Oskar Andero <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
Acked-by: Uwe Kleine-König <[email protected]>
Signed-off-by: Russell King <[email protected]>