usb_pd: Cleanup: Add functions to process Disc Identity
usb_pd: Cleanup: Add functions to process Disc Identity

Add separate functions process_am_discover_ident_sop() and
process_am_discover_ident_sop_prime() to process the Discover Identity
command.

BUG=b:148528713
BRANCH=none
TEST=make buildall -j

Signed-off-by: Ayushee <5730d7ed61dc96fa04bcc2bc2e4ce32af5b2c19d@intel.com>
Change-Id: Id074b2fc5c9aae02b51b110c9959656cacb36ee7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2185615
Commit-Queue: Keith Short <f6d578f97033c25f1206cb57d52f358974c82954@chromium.org>
Reviewed-by: Keith Short <f6d578f97033c25f1206cb57d52f358974c82954@chromium.org>

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