hg: jdk/sandbox: 8199705: Docs.gmk needs to be updated to remove the -html5 option

[chris.hegarty at oracle.com]

Changeset: ce86061aff12
Author:    bpatel
Date:      2018-03-26 21:30 -0700
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/ce86061aff12

8199705: Docs.gmk needs to be updated to remove the -html5 option
Reviewed-by: erikj

! make/Docs.gmk