control pthread support since some arches like x86_64 dont yet support it in uClibc

toolchain/Makefile.in

@@ -1,3 +1,9 @@
+ifeq ($(BR2_PTHREADS),y)
+THREADS:=--enable-threads
+else
+THREADS:=--disable-threads
+endif
+
 ifeq ($(BR2_ENABLE_MULTILIB),y)
 MULTILIB:=--enable-multilib
 else

toolchain/gcc/gcc-uclibc-3.x.mk

@@ -109,6 +109,7 @@ $(GCC_BUILD_DIR1)/.configured: $(GCC_DIR)/.patched
 		--enable-target-optspace \
 		--with-gnu-ld \
 		$(DISABLE_NLS) \
+		$(THREADS) \
 		$(MULTILIB) \
 		$(SOFT_FLOAT_CONFIG_OPTION) \
 		$(GCC_WITH_CPU) $(GCC_WITH_ARCH) $(GCC_WITH_TUNE) \
@@ -163,6 +164,7 @@ $(GCC_BUILD_DIR2)/.configured: $(GCC_DIR)/.patched $(STAGING_DIR)/lib/libc.a
 		--enable-target-optspace \
 		--with-gnu-ld \
 		$(DISABLE_NLS) \
+		$(THREADS) \
 		$(MULTILIB) \
 		$(SOFT_FLOAT_CONFIG_OPTION) \
 		$(GCC_WITH_CPU) $(GCC_WITH_ARCH) $(GCC_WITH_TUNE) \
@@ -279,6 +281,7 @@ $(GCC_BUILD_DIR3)/.configured: $(GCC_BUILD_DIR2)/.installed
 		--enable-target-optspace \
 		--with-gnu-ld \
 		$(DISABLE_NLS) \
+		$(THREADS) \
 		$(MULTILIB) \
 		$(SOFT_FLOAT_CONFIG_OPTION) \
 		$(GCC_WITH_CPU) $(GCC_WITH_ARCH) $(GCC_WITH_TUNE) \

toolchain/uClibc/Config.in

@@ -22,9 +22,16 @@ config BR2_ENABLE_LOCALE
 	help
 	    Enable locale/gettext/i18n support?
 
+config BR2_PTHREADS
+	bool "Enable thread support"
+	default y
+	help
+	    Enable support for libpthreads
+
 config BR2_PTHREADS_NATIVE
 	bool "Enable Native POSIX Threading (NPTL) support?"
 	default n
+	depends on BR2_PTHREADS
 	help
 	    Enable Native POSIX Threading (NPTL) support?