Lynx: add requirement for vendor_kernel_boot partition

Bug: 214409109
Signed-off-by: Lucas Wei <[email protected]>
Change-Id: If5b544370992f8d872a128177358fc6dfa3e928d

board-info.txt

@@ -1 +1,2 @@
 require board=lynx
+require partition-exists=vendor_kernel_boot