libc/mingw: threads are the native ones

There is no need to differentiate the win32 threads case, since we
can cosider them to be the native implementation on Windows.

Besides, with the previous patch, nothing uses it anymore.

So, just remove it.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc Bryan Hundven <bryanhundven@gmail.com>

config/libc.in

@@ -32,10 +32,6 @@ config LIBC_SUPPORT_THREADS_LT
     bool
     select LIBC_SUPPORT_THREADS_ANY
 
-config LIBC_SUPPORT_THREADS_WIN32
-    bool
-    select LIBC_SUPPORT_THREADS_ANY
-
 config LIBC_SUPPORT_THREADS_NONE
     bool
 
@@ -53,7 +49,6 @@ choice
     prompt "Threading implementation to use:"
     default THREADS_NATIVE         if LIBC_SUPPORT_THREADS_NATIVE
     default THREADS_THREADS_LT     if LIBC_SUPPORT_THREADS_LT && ! LIBC_SUPPORT_THREADS_NATIVE
-    default THREADS_WIN32          if LIBC_SUPPORT_THREADS_WIN32
     default THREADS_NONE           if ! LIBC_SUPPORT_THREADS_ANY
 
 config THREADS_NATIVE
@@ -64,18 +59,14 @@ config THREADS_NATIVE
       This selects the native threads implementation for the selected
       system and C library.
 
-      For example, on Linux with glibc, this is NPTL.
+      For example, on Linux with glibc, this is NPTL; on Windows with
+      mingw, this is win32.
 
 config THREADS_LT
     bool
     prompt "linuxthreads"
     depends on LIBC_SUPPORT_THREADS_LT
 
-config THREADS_WIN32
-    bool
-    prompt "win32"
-    depends on LIBC_SUPPORT_THREADS_WIN32
-
 config THREADS_NONE
     bool
     prompt "none"

config/libc/mingw.in

@@ -2,7 +2,7 @@
 
 ## depends on WINDOWS
 ##
-## select LIBC_SUPPORT_THREADS_WIN32
+## select LIBC_SUPPORT_THREADS_NATIVE
 ## select CC_CORE_PASSES_NEEDED
 ##
 ## help The de-facto standard for Mingw distributions.