RFR: JDK-8222926: Unify cpu related part of shenandoahBarrierSetC1 and fix build when compiler1 is disabled

[Ao Qi]

Hi,

When I configure using --with-jvm-features=-compiler1, I found build
is broken. The main cause is that some shenandoah related part did not
consider the situation when compiler1 is disabled. I also found that
src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetC1_aarch64.cpp
and src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetC1_x86.cpp
were basically the same, with only small differences. I unified these
two files and moved the result to a c1 related file. I also fixed one
"#undef" only when COMPILER1 is true in
shenandoahBarrierSetAssembler_x86/aarch64.cpp and one missed include
in codeBlob.cpp.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8222926/

Webrev:
http://cr.openjdk.java.net/~aoqi/8222926/webrev.00/

Tested:
  - build: linux-x86_64-{server, zero, minimal}-{release, fastdebug},
linux-aarch64-server-release
  - jtreg: linux-x86_64-server-release tier1,
linux-aarch64-server-release tier1_gc_shenandoah

Thanks,
Ao Qi