refspec: clarify function naming and documentation

refspec: clarify function naming and documentation

Rename `match_name_with_pattern()` to `match_refname_with_pattern()` to
better reflect its purpose and improve documentation comment clarity.
The previous function name and parameter names were inconsistent, making
it harder to understand their roles in refspec matching.

- Rename parameters:
  - `key` -> `pattern` (globbing pattern to match)
  - `name` -> `refname` (refname to check)
  - `value` -> `replacement` (replacement mapping pattern)

Signed-off-by: Meet Soni <meetsoni3017@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>