cortex-m/ec.ld.S: Remove explicitly allocated .data LMA sections.
cortex-m/ec.ld.S: Remove explicitly allocated .data LMA sections.

Overlapping LMA section with other VMA section will fail lld.
This CL makes the linker script to be compatible with both ld and lld.

BRANCH=None
BUG=b:128269393
TEST=On m/master; make buildall -j; mv build build.old
     After this CL:
     make buildall -j
     ls build/*/*/ec.*.smap | sed -e 's|build/||' | \
     xargs -I{} diff build/{} build.old/{}
     => no difference except that __data_lma_start's attribute changes
     from D to R.
     e.g., 0011a4a0 D __data_lma_start becomse
           0011a4a0 R __data_lma_start
TEST=diff build/kukui_scp/RW/ec.RW.flat build.old/kukui_scp/RW/ec.RW.flat
     are the same, except the version strings.
TEST=CC=clang make BOARD=kukui_scp and see that __bss_start and
     __data_lma_start not overlapping in kukui_scp/RW/ec.RW.smap
TEST=CC=clang make BOARD=nocturne_fp -j and build pass.

Change-Id: I4a6ece8d2279124e2797e0dc71b228a470f029d9
Signed-off-by: Yilun Lin <2f2733c7206ea2b76bd2db1905cc5e8a75841c48@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1514436
Commit-Ready: Tom Hughes <fc5c12f30a5ed2baa0581f44ee14ad1eb7b20d83@chromium.org>
Tested-by: Yilun Lin <2f2733c7206ea2b76bd2db1905cc5e8a75841c48@chromium.org>
Reviewed-by: Tom Hughes <fc5c12f30a5ed2baa0581f44ee14ad1eb7b20d83@chromium.org>
Reviewed-by: Jett Rink <9d4aef0593e6843318d99df31597fb6153b89787@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec