Fix build on some 32bit systems with strtoll()

Fix build on some 32bit systems with strtoll()
broken by r13429 that duplicated unportable portability code.

GCC exits with errors: integer constant is too large for 'long' type

nnnL constants are "long" and cannot hold 64bit integers on 32bit platforms.
Use LL suffix for 64bit constants for now. It remains to be seen how portable
that LL C++ extension is: https://gcc.gnu.org/onlinedocs/gcc/Long-Long.html

Also fixed INT64_MIN #define (missing parenthesis).