Debug and disentangle the literal cacheing in CC Mode

Debug and disentangle the literal cacheing in CC Mode

(Final Commit)

* lisp/progmodes/cc-engine.el (c-semi-trim-near-cache): Correct a comparison
with the wrong ...-limit variable.
(c-semi-pp-to-literal): Remove a wrong setting of c-lit-pos-cache-limit.
(c-full-get-near-cache-entry): Eliminate extravagant and unneeded coding.
(c-state-cache-init, c-record-parse-state-state): No longer manipulate
c-lit-pos-cache, which is no longer regarded as part of c-parse-state.

* lisp/progmodes/cc-mode.el (c-basic-common-init): Call
c-truncate-lit-pos-cache to initialize the literal cache.