style(posix): drop void argument list in syslog shim

modernize-redundant-void-arg flagged closelog(void) in the C++-only
shim. Drop the explicit (void) parameter list to match the rest of the
shim and silence the warning.

Signed-off-by: Nuno Marques <n.marques21@hotmail.com>

platforms/posix/include/windows_shim/syslog.h

@@ -100,7 +100,7 @@ static inline void openlog(const char *ident, int option, int facility)
 }
 
 /** @brief Close the syslog sink; no-op for the stderr-backed shim. */
-static inline void closelog(void) {}
+static inline void closelog() {}
 
 /**
  * @brief Set the active syslog priority mask.