soc/amd/picasso: record timestamps in psp_verstage

Verstage in PSP used stub for timestamps since we didn't know about
clock. Now we figured out clock source so we can enable timestamp
functions.

BRANCH=zork
BUG=b:154142138, b:159220781
TEST=build without CONFIG_PSP_VERSTAGE_FILE, flash and boot

Change-Id: I431a243878e265b68783f54ee9424bb1d4fe03c1
Signed-off-by: Kangheui Won <khwon@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45467
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/lib/Makefile.inc

@@ -68,10 +68,7 @@ verstage-y += libgcc.c
 verstage-y += memcmp.c
 verstage-y += string.c
 
-# TODO: Remove this when PSP bootblock timestamps are implemented.
-ifeq ($(CONFIG_VBOOT_STARTS_BEFORE_BOOTBLOCK),)
 verstage-$(CONFIG_COLLECT_TIMESTAMPS) += timestamp.c
-endif
 verstage-y += boot_device.c
 verstage-$(CONFIG_CONSOLE_CBMEM) += cbmem_console.c