tree e4b2f86b2bdd92c81f688ef61806c8545151ee55
parent 58aa86b1bda1c92327b53fe21d98be2680d95f1a
author Alex Van Damme <atv@google.com> 1547493549 -0800
committer Alex Van Damme <atv@google.com> 1547494702 -0800

Add arch.mk

- Add arch.mk, which is included from build/preamble.mk
- Define cache paths
- Add empty BOARD_PACKAGES_EXTRA
- Define BOOT/ROOTFS sizes

Change-Id: Ib04e3b74ee6d489875018d32b2c8a9b620dae82a