riscv: hwprobe.rst: Make indentation consistent

riscv: hwprobe.rst: Make indentation consistent

A handful of vendor-extension entries indent continuation lines with a
tab character, while the rest of hwprobe.rst uses spaces.  In addition,
many list items align their continuation lines under the 'm' of
':c:macro:' (column 7) rather than under the item text (column 4), so
the file mixes several indentation styles.

Replace the tabs with spaces and align every list item's continuation
lines under the item text, giving the whole file one consistent style.

Whitespace-only change, no functional change.

[Guodong: extend from tabs->spaces to normalizing all continuation-line
 indentation across the file]

Signed-off-by: Andrew Jones <andrew.jones@oss.qualcomm.com>
Signed-off-by: Guodong Xu <docular.xu@gmail.com>
Link: https://patch.msgid.link/20260701-rva23u64-hwprobe-v2-v5-2-2c61f94a695a@gmail.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>