msm: Make CONFIG_STRICT_MEMORY_RWX even stricter

If CONFIG_STRICT_MEMORY_RWX was set, the first section (containing
the kernel page table and the initial code) and the section
containing the init code were both given RWX permission, which is
a potential security hole.

Pad the first section after the initial code (which will never
be executed when the MMU is on) to make the rest of the kernel
text start in the second section and make the first section RW.

Move some data which had ended up in the "init text"
section into the "init data" one, as this is RW, not RX.
Make the "init text" RX.

We will not free the section containing the "init text",
because if we do, the kernel will allocate memory for RW data there.

Change-Id: I6ca5f4e07342c374246f04a3fee18042fd47c33b
CRs-fixed: 513919
Signed-off-by: Larry Bassel <lbassel@codeaurora.org>