[foreign-memaccess+abi] RFR: 8276647: Remove C2 trivial call intrinsification support

[Jorn Vernee]

Hi,

This patch removes the C2 support for trivial call intrinsification, which is currently unused. (see also the JBS issue for a brief discussion).

Besides all the code that is removed by this patch, there is one 'logical' change as well: currently we are encoding `VMStorage[]` as `long[]` in `NativeEntryPoint::make`, but this is no longer needed, and I now can pass the `VMStorage[]` to native code directly. This allows removing the `vmstorage_to_vmreg` & `vmStorageToVMReg` function pair. `parse_vmstorage` is used in the native code instead. (see the code changes in NativeEntryPoint.java & nativeEntryPoint.cpp).

Thanks,
Jorn

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Commit messages:
 - Remove spurious includes
 - Remove WeakReferenceCache for now
 - Rebase fixes
 - Remove more isTrivial, add WeakReferenceCache to NativeEntryPoint
 - Remove ciNativeEntryPoint
 - Remove C2 support for trivial native calls

Changes: https://git.openjdk.java.net/panama-foreign/pull/609/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=609&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8276647
  Stats: 739 lines in 48 files changed: 7 ins; 700 del; 32 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/609.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/609/head:pull/609

PR: https://git.openjdk.java.net/panama-foreign/pull/609