Add casts to CONF_HANDLE_T_U().
Add casts to CONF_HANDLE_T_U().

This avoids signed/unsigned comparison warnings when specifying integer
constants as inputs.

Clean up whitespace and add clarifying parentheses for
CONF_HANDLE_SIZE_T(opt_lg_chunk, ...).

wqfish/jemalloc,wqfish/jemalloc,wqfish/jemalloc,wqfish/jemalloc,wqfish/jemalloc