tanh: Use unary_decl instead of custom inc file

Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
Reviewed-By: Aaron Watry <awatry@gmail.com>
llvm-svn: 317259
GitOrigin-RevId: 91d7b92d8ae03db7ff8f58d7ca5d7c64427f03b8
2 files changed