drm/i915/guc: Clean up of register capture search

The comparison in the search for a matching register capture node was
not the most readable. It was also assuming that a zero GuC id means
invalid, which it does not. So remove one invalid term, one redundant
term and re-format to keep each term on a single line, and only one
term per line.

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230311063714.570389-3-John.C.Harrison@Intel.com