i3c: Restrict HDR modes to those supported by the bus and target

I3C v1.1.1 Table 9 defines which HDR Modes are permitted for each Bus
Configuration.  A Mixed Slow / Limited Bus permits no HDR Modes because
Legacy I2C Devices without a 50 ns SCL spike filter cannot be shielded
from HDR traffic.  A Mixed Fast Bus permits HDR-DDR and HDR-TSL, but not
HDR-TSP, since of the two Ternary Modes only HDR-TSL is defined for a Bus
that also has Legacy I2C Devices.

However, both i3c_device_get_supported_xfer_mode() and the transfer
validation in i3c_dev_do_xfers_locked() currently consider only the
controller's hdr_cap.  Since hdr_cap reflects controller capability
rather than bus or target constraints, HDR Modes can be advertised and
used even when the bus configuration forbids them.  Likewise, HDR Modes
unsupported by the target may be reported as available.

Add i3c_dev_supported_xfer_modes_locked(), which derives the usable
transfer modes from the intersection of:

  - HDR Modes supported by the controller
  - HDR Modes allowed by the bus configuration
  - HDR Modes supported by the target

Use this helper both when reporting supported transfer modes and when
validating transfers, ensuring that the advertised and permitted modes
remain consistent.

GETHDRCAP is queried only when I3C_BCR_HDR_CAP is set, so a target
without that bit is treated as supporting no HDR Modes.

i3c_device_get_supported_xfer_mode() now takes the normal-use bus lock
in order to access the device descriptor, matching
i3c_device_get_info().

Also fix the kernel-doc reference to enum i3c_xfer_mode.

Fixes: 256a21743d91 ("i3c: Add HDR API support")
Assisted-by: GitHub-Copilot:claude-opus-5
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260920151248.46936-17-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

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