remoteproc: qcom_q6v5_wcss: fix parsing of qcom,halt-regs

remoteproc: qcom_q6v5_wcss: fix parsing of qcom,halt-regs

The "qcom,halt-regs" consists of a phandle reference followed by the
three offsets within syscon for halt registers. Thus, we need to
request 4 integers from of_property_read_variable_u32_array(), with
the halt_reg ofsets at indexes 1, 2, and 3. Offset 0 is the phandle.

With MAX_HALT_REG at 3, of_property_read_variable_u32_array() returns
-EOVERFLOW, causing .probe() to fail.

Increase MAX_HALT_REG to 4, and update the indexes accordingly.

Fixes: 0af65b9b915e ("remoteproc: qcom: wcss: Add non pas wcss Q6 support for QCS404")
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Link: https://lore.kernel.org/r/20251129013207.3981517-1-mr.nuke.me@gmail.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>