- Fix struct definitions from new u-boot
  Environment data structure were renamed in v2020.04. Fix environment
  env_entry structure definitions.
- Remove memory setup functions
  Memory setup functions 'dram_init', 'get_effective_memsize' and
  'dram_init_banksize' are defined within mach-imx specific memory
  driver and thus removed here.
- Fix some device node names
  Some device nodes are renamed in underlying dtsi files. Fix
  references to these nodes.
- Fix SPL build
  fix include files used
  fix PMIC configuration settings to allow build with PMIC support.

Signed-off-by: Thomas Schaefer <thomas.schaefer@kontron.com>