config: remove PMEM, reduce FIMC1 alloc

Change-Id: Ib4cc67c085bb9deab6fe1e0bcc80688155bb5c3b
Revert "mach-px: Remove odd ION contigheap #ifndef"

This reverts commit 3d5cae35b7f709b350a3c9dffb6509f022008fd0.

Revert "mach-u1: Remove odd ION contigheap #ifndef"

This reverts commit b633aecacb5987b7023d4130a864a9bc1c65f247.

The explanation for these ifndefs has finally been determined:
Mobile's gralloc blobs take video memory from ION instead
of FIMC1 even when GRALLOC_USAGE_HW_FIMC1 is set.

Now that our gralloc emulate's Mobile's blobs, we don't
need FIMC1 memory.

Change-Id: I240ace09f1cda16d441dc4f3e24c546bd9b86cc5