Remove OS_LINUX_GENERIC

It was always defined (linux and android)

Test: TreeHugger
Bug: 279502784
Change-Id: If53c4ea123958b81b3e679ac64e9063bdc5a035c
diff --git a/system/BUILD.gn b/system/BUILD.gn
index 8a48153..9bd9514 100644
--- a/system/BUILD.gn
+++ b/system/BUILD.gn
@@ -116,7 +116,6 @@
   cflags_cc = [ "-std=c++17" ]
 
   defines = [
-    "OS_LINUX_GENERIC",
     "TARGET_FLOSS",
     "EXPORT_SYMBOL=__attribute__((visibility(\"default\")))",
     "FALLTHROUGH_INTENDED=[[clang::fallthrough]]",
diff --git a/system/gd/Android.bp b/system/gd/Android.bp
index 3808355..f0617f6 100644
--- a/system/gd/Android.bp
+++ b/system/gd/Android.bp
@@ -19,9 +19,6 @@
     target: {
         android: {
             test_config_template: "AndroidTestTemplate.xml",
-            cflags: [
-                "-DOS_LINUX_GENERIC",
-            ],
             shared_libs: [
                 "liblog",
             ],
@@ -29,11 +26,6 @@
                 misc_undefined: ["bounds"],
             },
         },
-        host: {
-            cflags: [
-                "-DOS_LINUX_GENERIC",
-            ],
-        },
         darwin: {
             enabled: false,
         },
diff --git a/system/gd/BUILD.gn b/system/gd/BUILD.gn
index 1d75f90..7acf521 100644
--- a/system/gd/BUILD.gn
+++ b/system/gd/BUILD.gn
@@ -26,7 +26,6 @@
   ]
 
   defines = [
-    "OS_LINUX_GENERIC",
     "TARGET_FLOSS",
   ]
 
diff --git a/system/gd/os/queue.h b/system/gd/os/queue.h
index cd8b554..57b04d5 100644
--- a/system/gd/os/queue.h
+++ b/system/gd/os/queue.h
@@ -25,9 +25,7 @@
 #include "common/bind.h"
 #include "common/callback.h"
 #include "os/handler.h"
-#ifdef OS_LINUX_GENERIC
 #include "os/linux_generic/reactive_semaphore.h"
-#endif
 #include "os/log.h"
 
 namespace bluetooth {
@@ -89,11 +87,9 @@
 
   class QueueEndpoint {
    public:
-#ifdef OS_LINUX_GENERIC
     explicit QueueEndpoint(unsigned int initial_value)
         : reactive_semaphore_(initial_value), handler_(nullptr), reactable_(nullptr) {}
     ReactiveSemaphore reactive_semaphore_;
-#endif
     Handler* handler_;
     Reactor::Reactable* reactable_;
   };
@@ -161,9 +157,7 @@
   common::OnceClosure callback_on_empty_;
 };
 
-#ifdef OS_LINUX_GENERIC
 #include "os/linux_generic/queue.tpp"
-#endif
 
 }  // namespace os
 }  // namespace bluetooth