Backing out some logic: Remove syslog functions from syscalls

include/syslog.h

@@ -49,25 +49,6 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
-/* Configuration ************************************************************/
-/* Some interfaces in this file are currently only available within the
- * kernel.  They could are available to applications in the flat build and
- * could be made available in the protected and kernel builds IF system
- * calls were added.
- *
- * REVISIT: For example, I don't yet know how to pass a va_list in a system
- * call so none of those interfaces.
- *
- * NOTE: In protected and kernel builds, there may also be a limit to the
- * number of parameters that are supported in the variable parameter list.
- */
-
-#if !defined(CONFIG_BUILD_PROTECTED) && !defined(CONFIG_BUILD_KERNEL)
-#  undef __KERNEL__
-#  define __KERNEL__ 1
-#endif
-
-/* syslog interface *********************************************************/
 /* The option argument to openlog() is an OR of any of these:
  *
  *   LOG_CONS     - Write directly to system console if there is an error
@@ -156,9 +137,7 @@ void closelog(void);
  */
 
 int syslog(int priority, FAR const char *format, ...);
-#ifdef __KERNEL__
 int vsyslog(int priority, FAR const char *src, va_list ap);
-#endif
 
 #ifdef CONFIG_ARCH_LOWPUTC
 /* These are non-standard, low-level system logging interface.  The
@@ -172,9 +151,7 @@ int vsyslog(int priority, FAR const char *src, va_list ap);
  */
 
 int lowsyslog(int priority, FAR const char *format, ...);
-#  ifdef __KERNEL__
 int lowvsyslog(int priority, FAR const char *format, va_list ap);
-#  endif
 
 #else
 /* If the platform cannot support lowsyslog, then we will substitute the
@@ -188,9 +165,7 @@ int lowvsyslog(int priority, FAR const char *format, va_list ap);
 #  else
 #    define lowsyslog (void)
 #  endif
-#  ifdef __KERNEL__
-#   define lowvsyslog(p,f,a) vsyslog(p,f,a)
-#  endif
+#  define lowvsyslog(p,f,a) vsyslog(p,f,a)
 #endif
 
 /* The setlogmask() function sets the logmask and returns the previous