flatbuffers: add 1.11.0 (spack#14663)

Author: matz-e

var/spack/repos/builtin/packages/flatbuffers/package.py

@@ -13,6 +13,7 @@ class Flatbuffers(CMakePackage):
     homepage = "http://google.github.io/flatbuffers/"
     url      = "https://github.com/google/flatbuffers/archive/v1.9.0.tar.gz"
 
+    version('1.11.0', sha256='3f4a286642094f45b1b77228656fbd7ea123964f19502f9ecfd29933fd23a50b')
     version('1.10.0', sha256='3714e3db8c51e43028e10ad7adffb9a36fc4aa5b1a363c2d0c4303dd1be59a7c')
     version('1.9.0', sha256='5ca5491e4260cacae30f1a5786d109230db3f3a6e5a0eb45d0d0608293d247e3')
     version('1.8.0', sha256='c45029c0a0f1a88d416af143e34de96b3091642722aa2d8c090916c6d1498c2e')