Spell C++11 as C++11, not C++0x.

We already require GCC 4.8+, so -std=c++11 should work fine.

Change-Id: I07d46d7dcccb695b5df97a702f0d5007fdff3385
Reviewed-on: https://boringssl-review.googlesource.com/8245
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index bd7f432..f85b439 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,7 +33,7 @@
 if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
   set(C_CXX_FLAGS "-Wall -Werror -Wformat=2 -Wsign-compare -Wmissing-field-initializers -ggdb -fvisibility=hidden")
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${C_CXX_FLAGS} -Wmissing-prototypes")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x ${C_CXX_FLAGS} -Wmissing-declarations")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 ${C_CXX_FLAGS} -Wmissing-declarations")
 elseif(MSVC)
   set(MSVC_DISABLED_WARNINGS_LIST
       "C4100" # 'exarg' : unreferenced formal parameter