Update cros_boot_mode to build against libchrome-180609

Literally just a version number change in the makefile.

CQ-DEPEND=I7213d5e52069b6bdf55b96ceda7321e693c6f962

BUG=chromium-os:38935
TEST=emerge-x86-mario cros_boot_mode

Change-Id: I6ec4acfa6ffec194abe0d65c558248e414e47ffc
Reviewed-on: https://gerrit.chromium.org/gerrit/43349
Commit-Queue: Chris Masone <cmasone@chromium.org>
Tested-by: Chris Masone <cmasone@chromium.org>
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
diff --git a/Makefile b/Makefile
index 2f341a6..72fa1be 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@
 # Pull in chromium os defaults
 include common.mk
 
-BASE_VER ?= 125070
+BASE_VER ?= 180609
 PC_DEPS = libchrome-$(BASE_VER)
 PC_CFLAGS := $(shell $(PKG_CONFIG) --cflags $(PC_DEPS))
 PC_LIBS := $(shell $(PKG_CONFIG) --libs $(PC_DEPS))