run: smarter timeouts for spawn_serial

Now the boot timeout is the test timeout divided by the minimum amount of boot
trials. The time that is consumed by boot trials is subtracted from the test
timeout.

fix #994
usb block: use generic block driver API (Fix #966)
Follow-up fix for "hw: basic support for ODROID"
framebuffer test: acpi_drv and pci_device_pd
acpi: print RMRR region (not just base)
vesa: explicitly request VBE 2.0 information

We also skip any non-direct-color modes now.