bootcount: Migrate CONFIG_SYS_BOOTCOUNT_ADDR

Migrate the users of CONFIG_SYS_BOOTCOUNT_ADDR to Kconfig.  We can
provide a default for BOOTCOUNT_AM33XX as that's a specific part of the
RTC in use.  We can also provide a default for ARCH_LS1043A and
ARCH_LS1021A as they had been previously calculated and their symbols
are in Kconfig.  In the case of other QE-enabled platforms, they are not
so we must update the relevant defconfig files.  The previous default
only applied in some cases, even on a specific SoC family.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Alex Kiernan <alex.kiernan@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>