Simultaneous support of CONFIG_MX6UL and CONFIG_MX6ULL

[Matthias Schiffer]

Hi everyone,

for the submission of support for our TQMa6UL/TQMa6ULL SoM family I've
been wondering if it would be desirable to allow U-Boot configs that
support both i.MX6UL and i.MX6ULL. This would allow us to reduce the
number of required defconfig variants for our SoMs significantly.

I had a look at the differences between these configurations, and most
of the code already treats both SoCs the same (lots of "#if
defined(CONFIG_MX6UL) || defined(CONFIG_MX6ULL)"). The differences are
sufficiently small that it seems easy to change them to use runtime
detection for the SoC variant (and maybe not even leave CONFIG_MX6UL
and CONFIG_MX6ULL as separate config symbols):

- MX6UL selects HAS_CAAM. Runtime detection should already work (will
double-check)
- Fuse support: Easy to switch to runtime detection
- mx6ul_pins.h vs. mx6ull_pins.h: Mostly identical. Only definitions
for GPIO5 differ (and none of the differing definitions are used at
all)

I can propose patches for these changes if you think that it is a good
idea.

Kind regards,
Matthias