Only boot to rockbox if the power button is hold sufficiently long.
For consistency, use the same mechanism as the OF:
- read PSWITCH 550000 times
- boot if PSWITCH=1 at least 400000 out of 550000 times
Only apply the delay if Volume Down is not hold,
so that the OF and RB delay don't cumulate.
Change-Id: I1e8a4cd108c56bf784fcf1c320f7a001ef161701
Change mkimxboot to use the common Makefile. This will fix the object file
clash when building libmkimxboot for linking with Rockbox Utility (will be
needed for FS#12402).
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@31261 a1c6a512-1295-4272-9138-f99709370657
