fixup: remove unneeded CMAKE_C_FLAGS
diff --git a/CMakeLists.txt b/CMakeLists.txt
index fc5931c..b0b2fef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -123,7 +123,6 @@
 # PRId64 (and others) at compile time, and links to libutil for getopt_long
 if(CMAKE_SYSTEM_NAME STREQUAL "OS400")
 	string(APPEND CMAKE_CXX_FLAGS " -D__STDC_FORMAT_MACROS")
-	string(APPEND CMAKE_C_FLAGS " -D__STDC_FORMAT_MACROS")
 	string(APPEND CMAKE_EXE_LINKER_FLAGS " -lutil")
 endif()