The XIP linker script has several problems:

- PAGE_ALIGNED_DATA is missing and is likely to end up somewhere with
  the wrong LMA.

- BUG_TABLE definitely has the wrong LMA, it is not copied to RAM, and
  its VMA is unaccounted for and likely to clash with dynamic memory
  usage.

- TCM usage is similarly broken.

- PERCPU_SECTION is left in ROM despite being written to.

Let's use generic macros for those things and locate them appropriately.
Incidentally, those macros are usable with a LMA != VMA already by
properly defining LOAD_OFFSET.

TCM is not fixed here. It never worked in a XIP configuration anyway, so
that can wait until another round of cleanups.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Chris Brandt <Chris.Brandt@renesas.com>