RFR: JDK-8199483 Clean up some non-standard LDFLAGS usage

[Magnus Ihse Bursie]

We have a few libraries that, for one reason or another, use 
non-standard LDFLAGS. There is typically no good reason for this, just 
historical accidents.

This patch fixes several places to remove odd or unneeded LDFLAGS, and 
to make them conform better to the prevailing standard. This will 
facilitate even more future cleanups in this area.

We still have some "snowflakes" left that have tricky LDFLAGS, but they 
require more research to figure out the best way to handle.

Some comments on the changes:
* -machine is not needed, it is autodetected by the linker.
* -subsystem:* has no meaning for dlls (and "windows" is default anyway)
* -map is always provided by SetupNativeCompilation
* -SAFESEH is provided by LDFLAGS_JDKLIB.
* The unknown symbols from libsaproc on Solaris was due to the missing 
link with libproc.
* In Windows DEF files, the HEAPSIZE command is equivalent to 
-heap:<nn>. But this is ignored for dlls. (We should not have any linker 
commands except EXPORTS in def files).

I'm running a COMPARE_BUILD set (it's 3/4 finished by now), to verify 
that there is no significant differences.

Bug: https://bugs.openjdk.java.net/browse/JDK-8199483
WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8199483-simplify-LDFLAGS/webrev.01

/Magnus