RFR: JDK-8069041: Bootcycle builds do not work with sjavac

[Erik Joelsson]

Hello,

Please review this small patch which fixes bootcycle-images builds when 
enabling sjavac. The problem was that the directory where the portfile 
should be created is never created in the bootcycle-build output 
directory. I think the best and simplest solution is to just always 
create it prior to running sjavac.

Bug: https://bugs.openjdk.java.net/browse/JDK-8069041
Patch inline:
diff -r 378fd58fe406 make/common/JavaCompilation.gmk
--- a/make/common/JavaCompilation.gmk
+++ b/make/common/JavaCompilation.gmk
@@ -538,7 +538,7 @@
$1_REMOTE:=--server:portfile=$$($1_SJAVAC_PORTFILE),id=$1,sjavac=$$(subst $$(SPACE),%20,$$(subst 
$$(COMMA),%2C,$$(strip $$($1_SERVER_JVM) $$($1_SJAVAC))))

      $$($1_BIN)/_the.$1_batch: $$($1_SRCS) $$($1_DEPENDS)
-    $(MKDIR) -p $$(@D)
+    $(MKDIR) -p $$(@D) $$(dir $$($1_SJAVAC_PORTFILE))
          # As a workaround for sjavac not tracking api changed from the 
classpath, force full
          # recompile if an external dependency, which is something 
other than a source
          # change, triggered this compilation.

/Erik