RFR: 8287393: AArch64: Remove trampoline_call1 [v2]

[Evgeny Astigeevich]

> `trampoline_call` can do dummy code generation to calculate the size of C2 generated code. This is done in the output phase. In [src/hotspot/cpu/aarch64/sharedRuntime_aarch64.cpp#L1042](https://github.com/openjdk/jdk/blob/e0d361cea91d3dd1450aece73f660b4abb7ce5fa/src/hotspot/cpu/aarch64/sharedRuntime_aarch64.cpp#L1042) Loom code needed to generate a trampoline call outside of C2 and without the output phase. This caused test crashes. The project Loom added `trampoline_call1` to workaround the crashes. 
> 
> This PR improves detection of C2 output phase which makes `trampoline_call1` redundant.
> 
> Tested the fastdebug/release builds:
> - `'gtest`: Passed
> - `tier1`...`tier2`: Passed

Evgeny Astigeevich has updated the pull request incrementally with one additional commit since the last revision:

  Replace trampoline_call1 with trampoline_call

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/9592/files
  - new: https://git.openjdk.org/jdk/pull/9592/files/8ba17f7b..e732890b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9592&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9592&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/9592.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9592/head:pull/9592

PR: https://git.openjdk.org/jdk/pull/9592