Fix WAIT_MORE_DATA during stream

[moticless]

Required to flush cache in the iterations of the loop that read global PEL as well.

Refactored and emphesis this operation with a distinct function:

/* Some of the element states are iterative in nature. For example, the parsing of
 * a list element is done by iterating over all its items, reading the next element
 * and calling to corresponding handler. The iteration usually starts by reading
 * from the RDB source and then enter into safe-state, process the data and usually
 * callback to corresponding handler. In that context, while the parser takes
 * care to flush the cache on transition to a new state such that the cache will
 * reflect only current state, instead of forcing each iteration to go back to the
 * parserMainLoop() and then return all the way back to the same element-state
 * for the next iteration, we can optimize the iterative states and make short
 * loop that will flush the cache internally at the end of each iteration, by
 * calling the following function and won't go back till the last iteration.
 *
 * By flushing the cache on each iteration, we ensure that if the state iteration
 * gets  interrupted in the middle, the parser can later resume the same interrupted
 * iteration of element state with a relevant cache that reflects only the
 * interrupted iteration. */
static inline RdbStatus updateElementStateIterative(RdbParser *p) {
    bulkPoolFlush(p);
    return RDB_STATUS_OK;
}

[oranagra]

i can't say i fully understand this. let's have a quick voice call so you can explain it to me.

[oranagra]

please update the top comment (for commit comment).
p.s. you moved some functions, which causes difficulties reviewing the diff and disrupts the blame log.. maybe it can be avoided.