hg: lanai/lanai: 8230042: Fix metal shader generation path

[jayathirth.d.v at oracle.com]

Changeset: d62427fd1866
Author:    jdv
Date:      2019-08-22 19:52 +0530
URL:       https://hg.openjdk.java.net/lanai/lanai/rev/d62427fd1866

8230042: Fix metal shader generation path
Reviewed-by: aghaisas

! make/lib/Awt2dLibraries.gmk