boost: fix uClibc-ng compile, from buildroot

package/boost/Makefile

@@ -6,7 +6,7 @@ include ${ADK_TOPDIR}/rules.mk
 PKG_NAME:=		boost
 PKG_VERSION:=		1.61.0
 PKG_EXTRAVER:=		1_61
-PKG_RELEASE:=		1
+PKG_RELEASE:=		2
 PKG_HASH:=		a77c7cc660ec02704c6884fbb20c552d52d60a18f26573c9cee0788bf00ed7e6
 PKG_DESCR:=		portable c++ library
 PKG_SECTION:=		libs/misc

package/boost/patches/patch-boost_config_platform_linux_hpp

@@ -0,0 +1,16 @@
+--- boost_1_61_0.orig/boost/config/platform/linux.hpp	2016-05-05 23:11:02.000000000 +0200
++++ boost_1_61_0/boost/config/platform/linux.hpp	2016-06-09 23:47:13.099272614 +0200
+@@ -46,6 +46,13 @@
+ 
+ #endif
+ 
++// uClibc has no support for fenv.h, and also a few architectures
++// don't have fenv.h support at all (or incomplete support) even with
++// glibc.
++#if defined(__UCLIBC__) || defined(__nios2__) || defined(__microblaze__)
++#  define BOOST_NO_FENV_H
++#endif
++
+ //
+ // If glibc is past version 2 then we definitely have
+ // gettimeofday, earlier versions may or may not have it: