Remove lockfile from global variables

Lock file business is handled by platform-specific helpers, this copy of the
filename is unused.

PiperOrigin-RevId: 250530444

src/main/cpp/blaze.cc

diff --git a/src/main/cpp/blaze.cc b/src/main/cpp/blaze.cc
index 5858970..ac4101f 100644
--- a/src/main/cpp/blaze.cc
+++ b/src/main/cpp/blaze.cc
@@ -1180,8 +1180,6 @@
         << "') failed: " << GetLastErrorString();
   }
 
-  globals->lockfile =
-      blaze_util::JoinPath(globals->options->output_base, "lock");
   if (!globals->options->server_jvm_out.empty()) {
     globals->jvm_log_file = globals->options->server_jvm_out;
     globals->jvm_log_file_append = true;

src/main/cpp/global_variables.h

diff --git a/src/main/cpp/global_variables.h b/src/main/cpp/global_variables.h
index 4ea590e..458bba3 100644
--- a/src/main/cpp/global_variables.h
+++ b/src/main/cpp/global_variables.h
@@ -50,9 +50,6 @@
     return extracted_binaries.empty() ? "" : extracted_binaries[0];
   }
 
-  // Used to make concurrent invocations of this program safe.
-  std::string lockfile;  // = <output_base>/lock
-
   // Whrere to write the server's JVM's output. Default value is
   // <output_base>/server/jvm.out.
   std::string jvm_log_file;