mainboard/intel: Add MinnowBoard 3

This commit adds the initial scaffolding for the MinnowBoard 3
with Apollo Lake silicon.

This mainboard is based on Intel's Leafhill CRB with Apollo Lake
silicon. In a first step, it concerns only a copy of intel/leafhill
directory with name changes. Special adaptations for MinnowBoard 3
mainboard will follow in separate commits.

Change-Id: I7563fe37c89511c7035c5bffc9b034b379cfcaf4
Signed-off-by: Brenton Dong <brenton.m.dong@intel.com>
Reviewed-on: https://review.coreboot.org/18298
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/mainboard/intel/minnow3/board_info.txt b/src/mainboard/intel/minnow3/board_info.txt
new file mode 100644
index 0000000..0b891a2
--- /dev/null
+++ b/src/mainboard/intel/minnow3/board_info.txt
@@ -0,0 +1,6 @@
+Vendor name: Intel
+Board name: MinnowBoard 3
+Category: eval
+ROM protocol: SPI
+ROM socketed: n
+Flashrom support: y