RFR: 8308544: Fix compilation regression from JDK-8306983 on musl libc

[Jan Kratochvil]

Since [JDK-8306983](https://bugs.openjdk.org/browse/JDK-8306983) compilation on Alpine Linux using musl libc:

../src/jdk.internal.le/linux/native/lible/CLibrary.cpp: In function 'void Java_jdk_internal_org_jline_terminal_impl_jna_linux_CLibraryImpl_tcgetattr(JNIEnv*, jobject, jint, jobject)':
../src/jdk.internal.le/linux/native/lible/CLibrary.cpp:116:45: error: 'struct termios' has no member named 'c_ispeed'; did you mean '__c_ispeed'?
  116 | env->SetIntField(result, c_ispeed, data.c_ispeed);
      | ^~~~~~~~
      | __c_ispeed
../src/jdk.internal.le/linux/native/lible/CLibrary.cpp:117:45: error: 'struct termios' has no member named 'c_ospeed'; did you mean '__c_ospeed'?
  117 | env->SetIntField(result, c_ospeed, data.c_ospeed);
      | ^~~~~~~~
      | __c_ospeed
../src/jdk.internal.le/linux/native/lible/CLibrary.cpp: In function 'void Java_jdk_internal_org_jline_terminal_impl_jna_linux_CLibraryImpl_tcsetattr(JNIEnv*, jobject, jint, jint, jobject)':
../src/jdk.internal.le/linux/native/lible/CLibrary.cpp:136:10: error: 'struct termios' has no member named 'c_ispeed'; did you mean '__c_ispeed'?
  136 | data.c_ispeed = env->GetIntField(input, c_ispeed);
      | ^~~~~~~~
      | __c_ispeed
../src/jdk.internal.le/linux/native/lible/CLibrary.cpp:137:10: error: 'struct termios' has no member named 'c_ospeed'; did you mean '__c_ospeed'?
   ... (rest of output omitted)

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

Commit messages:
 - 8308544: Fix compilation regression from JDK-8306983 on musl libc

Changes: https://git.openjdk.org/jdk/pull/14080/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14080&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8308544
  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/14080.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14080/head:pull/14080

PR: https://git.openjdk.org/jdk/pull/14080