archivers/pecl-rar: fix build on 32-bits

/wrkdirs/usr/ports/archivers/pecl-rar/work-php82/rar-4.2.0/rararch.c:1237:42: error: incompatible function pointer types assigning to 'zend_object_count_elements_t' (aka 'ZEND_RESULT_CODE (*)(struct _zend_object *, int *)') from 'int (handler_this_t *, long *)' (aka 'int (struct _zend_object *, long *)') [-Wincompatible-function-pointer-types]