abseil-cpp: remove -Dcmake_cxx_standard=14 flag from extra_oecmake

Old versions of abseil-cpp could not be compiled using C++ Standard 17.
For now this cmake flag is not needed.
Mosh compilation fixed by specifying c++17 standard.

Signed-off-by: Petr Chernikov <p.chernikov@yadro.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-devtools/abseil-cpp/abseil-cpp_git.bb

@@ -27,7 +27,6 @@ inherit cmake
 
 EXTRA_OECMAKE = "-DBUILD_SHARED_LIBS=ON \
                  -DBUILD_TESTING=OFF    \
-                 -DCMAKE_CXX_STANDARD=14 \
                  -DABSL_ENABLE_INSTALL=ON \
                 "