soc/intel/apollolake: Add support to log XHCI wake events

Add support to identify and log the XHCI wake events for apollolake into
event logs.

BUG=b:123429132
BRANCH=None
TEST=Ensure that the system boots to ChromeOS. Ensure that the wake up
events due to USB are logged into the event logs.
6 | 2019-03-21 09:22:18 | S0ix Enter
7 | 2019-03-21 09:22:22 | S0ix Exit
8 | 2019-03-21 09:22:22 | Wake Source | PME - XHCI (USB 2.0 port) | 9
9 | 2019-03-21 09:22:22 | Wake Source | GPE # | 13
10 | 2019-03-21 09:23:20 | ACPI Enter | S3
11 | 2019-03-21 09:23:30 | Wake Source | PME - XHCI (USB 2.0 port) | 9
12 | 2019-03-21 09:23:30 | ACPI Wake | S3
13 | 2019-03-21 09:23:30 | Wake Source | GPE # | 13

Change-Id: I55b850646dda8acaa086a9012c2d8b611016f932
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32000
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/soc/intel/apollolake/Kconfig b/src/soc/intel/apollolake/Kconfig
index 19cd296..d715f39 100644
--- a/src/soc/intel/apollolake/Kconfig
+++ b/src/soc/intel/apollolake/Kconfig
@@ -94,6 +94,7 @@
 	select SOC_INTEL_COMMON_BLOCK_UART
 	select SOC_INTEL_COMMON_BLOCK_XDCI
 	select SOC_INTEL_COMMON_BLOCK_XHCI
+	select SOC_INTEL_COMMON_BLOCK_XHCI_ELOG
 	select SOC_INTEL_COMMON_BLOCK_SMM
 	select SOC_INTEL_COMMON_BLOCK_SPI
 	select SOC_INTEL_COMMON_BLOCK_CSE