git: openjdk/mobile: 8243059: Build fails when --with-vendor-name contains a comma

[duke]

Changeset: 85d07da4
Author:    Severin Gehwolf <sgehwolf at openjdk.org>
Date:      2020-04-17 11:14:17 +0000
URL:       https://git.openjdk.java.net/mobile/commit/85d07da4

8243059: Build fails when --with-vendor-name contains a comma

Use $$(VERSION_CFLAGS) so as to avoid the variable getting evaluated early

Reviewed-by: ihse, erikj

! make/launcher/LauncherCommon.gmk