Fixes #1437

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

- Add a board README to explain how to get Infix running
- Update mkimage.sh to allow creating images without boot loader

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

Inverted values for eMMC and SPI NAND.  Also use ABCD instead of
Position as column name to match board markings.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

NOTE: this is intended only for use on devboards like EspressoBin where
      the onboard bootloader only understands fat and ext2 file systems.
      To enable, use 'make apply-ext4'

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

This is used by the next commit that adds initial support for PTP/gPTP.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

Remaining work:
- phc2sys YANG model (infix-phc2sys.yang, instance-index + servo params)
- ts2phc YANG model (GPS/PPS → PHC → ptp4l GM path)
- timemaster coordination (Phase 3, after phc2sys YANG is stable)
- show ptp network (YANG action or background-polled topology container)
- CMLDS (requires upstream linuxptp + 802.1ASdm foundation)
- Full 12-bit sdoId, fault log, performance monitoring

Backported patches from linuxptp master:
- port: fix unicast negotiation recovery after FAULT_DETECTED
- udp: fix port-specific ptp/p2p_dst_ipv4 configuration
- pmc: avoid race conditions in agent update
- phc2sys: wait until pmc agent is subscribed (startup race)
- fix MAC driver incorrect SIOCGHWTSTAMP adjustment flags
- pmc_agent: longer update interval when not subscribed
- phc2sys: don't disable pmc agent with -s/-d/-w options
- port_signaling: respect ptp_minor_version in message header
- port: refresh link status on faults
- uds: copy server socket ownership in pmc clients (non-root pmc)
- uds: don't call chmod() on client socket
- port: allow mixing wildcard and exact clock identities
- Add pidfile support to ptp4l, phc2sys, and timemaster

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

On multi-chip DSA hardware (e.g., boards with multiple mv88e6xxx
chips), each switch chip has its own independent PHC device.  With
boundary_clock_jbod enabled, ptp4l starts but only disciplines the
active slave port's PHC — the others drift.

Automatically start phc2sys -a alongside any BC or TC instance using
hardware timestamping.  It subscribes to ptp4l's UDS socket, tracks
BMCA, and disciplines all non-active PHCs to match the active one.
On single-chip hardware it is a harmless no-op.

CLOCK_REALTIME is intentionally left untouched.  Syncing the system
clock to PTP (phc2sys -rr), feeding the PHC from GPS/NTP (ts2phc,
phc2sys reverse), and full multi-source coordination (timemaster) are
planned as follow-on phases; see the issue tracker for the roadmap.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>