boot/nxboot: fix compile errors caused by nxboot_progress

Function nxboot_progress is located in nxboot_main.c, but this file
is not compiled when NXboot is used as a library to an existing
application and not as a bootloader. Therefore, the declaration of
nxboot_progress function should be dependent on NXBOOT_PROGRESS
config option.

Signed-off-by: Michal Lenc <michallenc@seznam.cz>

boot/nxboot/Kconfig

@@ -122,9 +122,14 @@ config NXBOOT_PREVENT_DOWNGRADE
 		WARNING: NXboot currently implements preferences only for
 		MAJOR.MINOR.PATCH and ignores prerelease.
 
+config NXBOOT_PROGRESS
+	bool
+	default n
+
 config NXBOOT_PRINTF_PROGRESS
 	bool "Enable progress messages to be sent to STDOUT"
 	default y
+	select NXBOOT_PROGRESS
 	---help---
 		This will display progress during typically lengthy operations:
 			- Calculating checksums

boot/nxboot/include/nxboot.h

@@ -168,7 +168,11 @@ enum progress_msg_e
  * Public Function Prototypes
  ****************************************************************************/
 
+#ifdef CONFIG_NXBOOT_PROGRESS
 void nxboot_progress(enum progress_type_e type, ...);
+#else
+#define nxboot_progress(type, ...) do {} while (0)
+#endif
 
 /****************************************************************************
  * Name: nxboot_get_state

boot/nxboot/nxboot_main.c

@@ -41,10 +41,12 @@
  * Public Data
  ****************************************************************************/
 
+#ifdef CONFIG_NXBOOT_PROGRESS
 static bool g_progress_started = false;
 #ifdef CONFIG_NXBOOT_PRINTF_PROGRESS_PERCENT
 static bool g_progress_percent_started = false;
 #endif
+#endif
 
 /****************************************************************************
  * Private Data
@@ -121,6 +123,7 @@ static const char *progress_msgs[] =
  *
  ****************************************************************************/
 
+#ifdef CONFIG_NXBOOT_PROGRESS
 void nxboot_progress(enum progress_type_e type, ...)
 {
 #ifdef CONFIG_NXBOOT_PRINTF_PROGRESS
@@ -242,6 +245,7 @@ void nxboot_progress(enum progress_type_e type, ...)
   va_end(arg);
 #endif /* CONFIG_NXBOOT_PRINTF_PROGRESS */
 }
+#endif
 
 /****************************************************************************
  * Name: nxboot_main