spl: Disable printf if not required

Now we have a guard for printf, disable it in the build if it's not
selected.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>

lib/panic.c

@@ -37,9 +37,11 @@ void panic_str(const char *str)
 
 void panic(const char *fmt, ...)
 {
+#if CONFIG_IS_ENABLED(PRINTF)
 	va_list args;
 	va_start(args, fmt);
 	vprintf(fmt, args);
 	va_end(args);
+#endif
 	panic_finish();
 }

lib/tiny-printf.c

@@ -23,11 +23,6 @@ struct printf_info {
 	void (*putc)(struct printf_info *info, char ch);
 };
 
-static void putc_normal(struct printf_info *info, char ch)
-{
-	putc(ch);
-}
-
 static void out(struct printf_info *info, char c)
 {
 	*info->bf++ = c;
@@ -321,6 +316,12 @@ abort:
 	return 0;
 }
 
+#if CONFIG_IS_ENABLED(PRINTF)
+static void putc_normal(struct printf_info *info, char ch)
+{
+	putc(ch);
+}
+
 int vprintf(const char *fmt, va_list va)
 {
 	struct printf_info info;
@@ -343,6 +344,7 @@ int printf(const char *fmt, ...)
 
 	return ret;
 }
+#endif
 
 static void putc_outstr(struct printf_info *info, char ch)
 {

lib/vsprintf.c

@@ -783,6 +783,7 @@ int sprintf(char *buf, const char *fmt, ...)
 	return i;
 }
 
+#if CONFIG_IS_ENABLED(PRINTF)
 int printf(const char *fmt, ...)
 {
 	va_list args;
@@ -824,7 +825,7 @@ int vprintf(const char *fmt, va_list args)
 	puts(printbuffer);
 	return i;
 }
-
+#endif
 
 void __assert_fail(const char *assertion, const char *file, unsigned line,
 		   const char *function)