mips/crc32: remove unused enums

mips/crc32: remove unused enums

Remove enum crc_op_size and enum crc_type, since they are never actually
used.  Tokens with the names of the enum values do appear in the file,
but they are only used for token concatenation with the preprocessor.

This prevents a conflict with the addition of crc32c() to linux/crc32.h.

Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/r/20250207224233.GA1261167@ax162
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250208024911.14936-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>