[ci skip] Update changelog

UPGRADING.INTERNALS

@@ -201,7 +201,7 @@ PHP 7.4 INTERNALS UPGRADE NOTES
     - Local PHP m4 unused or obsolete macros have been removed:
       PHP_TARGET_RDYNAMIC, PHP_SOLARIS_PIC_WEIRDNESS, PHP_SYS_LFS,
       PHP_AC_BROKEN_SPRINTF, PHP_EXTENSION, PHP_DECLARED_TIMEZONE,
-      PHP_CHECK_TYPES, PHP_TM_GMTOFF.
+      PHP_CHECK_TYPES, PHP_TM_GMTOFF, PHP_CHECK_64BIT.
     - new --enable-rtld-now build option allow to switch dlopen behavior
       from RTLD_LAZY to RTLD_NOW
     - Minimum Bison version is 3.0+ for generating parser files.