libc: Fix non-NPTL threads build

This patch fixes some issues building uclibc with linuxthreads, that seem to have
been introduced by the NPTL changes.

Signed-off-by: Andrew Stubbs <ams@codesourcery.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>

libc/misc/internals/__uClibc_main.c

@@ -36,7 +36,9 @@
 #include <not-cancel.h>
 #include <atomic.h>
 #endif
-
+#ifdef __UCLIBC_HAS_THREADS__
+#include <pthread.h>
+#endif 
 
 #ifndef SHARED
 void *__libc_stack_end = NULL;