[TESTBUG] Fix tests for OS with 64K page size.

Linux with ppc64 can be compiled to run with 64K pages per default. This spoils
a row of tests:

runtime/whitebox/WBStackSize.java
  The constant esimating the so far occupied stack is too small. Fix: Consider size of shadow pages

compiler/uncommontrap/TestStackBangRbp.java:
compiler/uncommontrap/TestStackBangMonitorOwned.java
compiler/uncommontrap/StackOverflowGuardPagesOff.java
compiler/uncommontrap/8009761/Test8009761.java
compiler/runtime/6865265/StackOverflowBug.java
compiler/exceptions/TestRecursiveReplacedException.java
 Increase stack size to 392K, need at least 328K.

sanity/ExecuteInternalVMTests.java
 - Assertion in metaspace.cpp simly must fail with vm_page_size == 64K as it
   basically asserts vm_page_size < 16K

gc/arguments/TestMaxHeapSizeTools.java
  Sizes are alinged up being equal in the end. Choose bigger sizes.

gc/g1/TestHumongousAllocInitialMark.java
  Test computes some size based on the -Xmx value it uses. Heap size is increased slightly
  with 64K making the computation wrong and the test fail. Choose heap size that needs not
  be aligned.

gc/g1/TestGCLogMessages.java
  Heap of 10M is increased to 32M because of the alignment with 64K pages.
  This makes the evacuation succeed. Choose 32M from the beginning and adapt
  size of huge object.