Add closing quotes for CFLAGS and CXXFLAGS

-CFLAGS="-O2 -pipe -march=native   CXXFLAGS="-O2 -pipe -march=native  LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,-O1 -Wl,--hash-style=gnu -Wl,--sort-common"
+CFLAGS="-O2 -pipe -march=native"   CXXFLAGS="-O2 -pipe -march=native"  LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,-O1 -Wl,--hash-style=gnu -Wl,--sort-common"