[riscv-port] RFR: 8277392: riscv: Port missing trampoline logic from AArch64 platform

[zhengxiaolinX]

Hi team,

Java calls will jump to the trampoline stub even if the target address is directly reachable by using a simple `jal` before this patch. After adding back the logic from the AArch64 platform, we find a nearly 4% performance enhancement on SPECjbb2005/15. Tested tests under hotspot/ and jdk/. [Original Patch](https://github.com/riscv-collab/riscv-openjdk/pull/8)

Thanks,
Xiaolin

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Commit messages:
 - Port optimization for trampoline call patching logic

Changes: https://git.openjdk.java.net/riscv-port/pull/8/files
 Webrev: https://webrevs.openjdk.java.net/?repo=riscv-port&pr=8&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8277392
  Stats: 6 lines in 1 file changed: 4 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/riscv-port/pull/8.diff
  Fetch: git fetch https://git.openjdk.java.net/riscv-port pull/8/head:pull/8

PR: https://git.openjdk.java.net/riscv-port/pull/8