Add native configurations for SunOS

[am11]

• grep does not support -o or -m options (only GNU-derived grep do)
  • replace grep -o with awk matching pattern, that works with Linux, macOS and BSD alike.
  • replace find $dir | grep -m 1 key with find $dir -name key | head -n1
• add basic configurations to get passed libraries and coreclr cmake configuration steps.
  • installer build succeeds with this change and the previously merged PR:

    src/installer/corehost/build.sh -apphostver 5.0.0-dev -hostver 5.0.0-dev -fxrver 5.0.0-dev -policyver 5.0.0-dev -commithash $(git rev-parse HEAD) -gcc

Contributes to: #4173

[ghost]

Tagging @ViktorHofer as an area owner

[jkotas]

Could you please take a look at the conflicts?

[am11]

Rebased and resolved merge conflicts.
Some legs are pending for 15 hours (#34832).

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