HADOOP-12972. Lz4Compressor#getLibraryName returns the wrong version number (cmccabe)

(cherry picked from commit e3d15a2e236f93325c67f9e52fb16f645c44238a)
(cherry picked from commit 9df2e54160d3d959138857757d2d64d595b54093)

hadoop-common-project/hadoop-common/src/main/native/src/org/apache/hadoop/io/compress/lz4/Lz4Compressor.c

@@ -87,7 +87,9 @@ JNIEXPORT jstring JNICALL
 Java_org_apache_hadoop_io_compress_lz4_Lz4Compressor_getLibraryName(
  JNIEnv *env, jclass class
  ) {
-  return (*env)->NewStringUTF(env, "revision:99");
+  char version_buf[128];
+  snprintf(version_buf, sizeof(version_buf), "revision:%d", LZ4_versionNumber());
+  return (*env)->NewStringUTF(env, version_buf);
 }
 
 JNIEXPORT jint JNICALL Java_org_apache_hadoop_io_compress_lz4_Lz4Compressor_compressBytesDirectHC