RFR: JDK-8055096: Remove explicit mx flag from javadoc command line

[Tim Bell]

Hi Erik:

> Please review this small patch. In Javadoc.gmk the javadoc command is 
> defined with an explicit mx flag. However, configure is already 
> calculating a suitable mx for a "large" java process, which is already 
> provided in the JAVA variable. This patch removes the redundant mx 
> flag from Javadoc.gmk.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8055096
> Patch inline:
>
> diff -r dbb964d72f25 make/Javadoc.gmk
> --- a/make/Javadoc.gmk
> +++ b/make/Javadoc.gmk
> @@ -52,7 +52,6 @@
>  BUILD_NUMBER=$(JDK_BUILD_NUMBER)
>
>  JAVADOC_CMD = $(JAVA) \
> -    -Xmx1024m \
>      -Djava.awt.headless=true \
>      $(NEW_JAVADOC) \
>      -bootclasspath $(JDK_OUTPUTDIR)/classes

Looks good.  Approved.

Tim