Drop unused PHP7ISAPI_EXPORTS

These definitions are usually used to distinguish between `dllexport`
and `dllimport`, but there is no need for `dllimport`, and we don't
use `dllexport` to specify the visible functions, but rather rely on a
.def file, since the Microsoft ISAPI headers predeclare the functions,
so the `dllexport` name mangling would cause link errors.

Author: cmb69

sapi/isapi/config.w32

@@ -6,7 +6,7 @@ if (PHP_ISAPI == "yes") {
 	if (PHP_ZTS == "no") {
 		WARNING("ISAPI module requires an --enable-zts build of PHP");
 	} else {
-		SAPI('isapi', 'php_isapi.c', 'php' + PHP_VERSION + 'isapi.dll', '/D PHP7ISAPI_EXPORTS /DZEND_ENABLE_STATIC_TSRMLS_CACHE=1');
+		SAPI('isapi', 'php_isapi.c', 'php' + PHP_VERSION + 'isapi.dll', '/DZEND_ENABLE_STATIC_TSRMLS_CACHE=1');
 		ADD_FLAG('LDFLAGS_ISAPI', '/DEF:sapi\\isapi\\php_isapi.def');
 	}
 }