msm: ipa4: Make AP and modem hdr proc ctx adjacent

APPS and modem header processing contexts SRAM areas
must be adjacent as H/W refer to them as single SRAM
area. This change removes the 8 bytes canary between
them.

CRs-Fixed: 2327596
Change-Id: I0056fe2b1eeb97841b99f7253bd8d5bf1d93149d
Signed-off-by: Ghanim Fodi <gfodi@codeaurora.org>