portability: Remove C99-illegal semicolons from the global scope

This commit touches the C codebase and the python syscall generator.

The Z_GENLIST-macros expand to whole functions. Once expanded by the
preprocessor we notice a semicolon is put after the function body. But
ISO C99 does not allow extra ‘;’ outside of a function. Though this is
accepted by GCC with GNU extensions, it is not by Clang.

Signed-off-by: Mark Ruvald Pedersen <mped@oticon.com>
diff --git a/scripts/gen_syscalls.py b/scripts/gen_syscalls.py
index e385f94..c919802 100755
--- a/scripts/gen_syscalls.py
+++ b/scripts/gen_syscalls.py
@@ -147,7 +147,7 @@
     flat_args = [sys_id, func_name] + flat_args
     argslist = ", ".join(flat_args)
 
-    invocation = "%s(%s);" % (macro, argslist)
+    invocation = "%s(%s)" % (macro, argslist)
 
     handler = "_handler_" + func_name