[glibmm] gmmproc: CONV_ENUM: Use static_cast<>.

[Murray Cumming <murrayc src gnome org>]

commit cff8661d61575b4d12b562ba8d56e9333d5d1c85
Author: Murray Cumming <murrayc murrayc com>
Date:   Sat May 6 23:16:18 2017 +0200

    gmmproc: CONV_ENUM: Use static_cast<>.

 tools/m4/convert_base.m4 |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/tools/m4/convert_base.m4 b/tools/m4/convert_base.m4
index ce447cc..b765758 100644
--- a/tools/m4/convert_base.m4
+++ b/tools/m4/convert_base.m4
@@ -55,10 +55,10 @@ define(`__ARG3__',`$`'3')
 # Specify C_enum_name, if it's not the concatenation of namespace+enum_name.
 define(`_CONV_ENUM',`dnl
 pushdef(`C_ENUM_NAME', `m4_ifelse(`$3',,`$1$2',`$3')')
-_CONVERSION(`C_ENUM_NAME', `$2', (($2)(__ARG3__)))
-_CONVERSION(`C_ENUM_NAME', `$1::$2', (($1::$2)(__ARG3__)))
-_CONVERSION(`$2', `C_ENUM_NAME', ((C_ENUM_NAME)(__ARG3__)))
-_CONVERSION(`$1::$2', `C_ENUM_NAME', ((C_ENUM_NAME)(__ARG3__)))
+_CONVERSION(`C_ENUM_NAME', `$2', static_cast<$2>(__ARG3__))
+_CONVERSION(`C_ENUM_NAME', `$1::$2', static_cast<$1::$2>(__ARG3__))
+_CONVERSION(`$2', `C_ENUM_NAME', static_cast<C_ENUM_NAME>(__ARG3__))
+_CONVERSION(`$1::$2', `C_ENUM_NAME', static_cast<C_ENUM_NAME>(__ARG3__))
 popdef(`C_ENUM_NAME')
 ')dnl