revert strange change in nsh Make.defs

nuttx-configs/px4fmu-v2/nsh/Make.defs

@@ -90,7 +90,7 @@ else
     ARCHXXINCLUDES	 = -I. -isystem $(TOPDIR)/include -isystem $(TOPDIR)/include/cxx
     ARCHSCRIPT		 = -T$(TOPDIR)/configs/$(CONFIG_ARCH_BOARD)/scripts/$(LDSCRIPT)
   else
-    # Linux/Cygwin-native toolchain
+    # Linux/Cygwin-native toolchain 
     MKDEP		 = $(TOPDIR)/tools/mkdeps.sh
     ARCHINCLUDES	 = -I. -isystem $(TOPDIR)/include
     ARCHXXINCLUDES	 = -I. -isystem $(TOPDIR)/include -isystem $(TOPDIR)/include/cxx
@@ -117,7 +117,7 @@ ARCHOPTIMIZATION	+= -g
 endif
 
 ARCHCFLAGS		 = -std=gnu99
-ARCHCXXFLAGS		 = -fno-exceptions -fno-rtti -std=c++11
+ARCHCXXFLAGS		 = -fno-exceptions -fno-rtti -std=gnu++0x
 ARCHWARNINGS		 = -Wall \
 			   -Wno-sign-compare \
 			   -Wextra \