logging: Add option LOG_MSG_APPEND_RO_STRING_LOC

Bring back Kconfig option which was previously removed by
9cd5086 (previously named LOG_MSG_PKG_ALWAYS_ADD_RO_STRING_IDXS).
Renamed to shorten and be more descriptive. It can be useful for
external backends or frontends.

Signed-off-by: Krzysztof Chruscinski <[email protected]>

Author: nordic-krch

include/zephyr/logging/log_msg.h

@@ -139,7 +139,9 @@ enum z_log_msg_mode {
 }
 
 #define Z_LOG_MSG2_CBPRINTF_FLAGS(_cstr_cnt) \
-	(CBPRINTF_PACKAGE_FIRST_RO_STR_CNT(_cstr_cnt))
+	(CBPRINTF_PACKAGE_FIRST_RO_STR_CNT(_cstr_cnt) | \
+	(IS_ENABLED(CONFIG_LOG_MSG_APPEND_RO_STRING_LOC) ? \
+	 CBPRINTF_PACKAGE_ADD_STRING_IDXS : 0))
 
 #ifdef CONFIG_LOG_USE_VLA
 #define Z_LOG_MSG2_ON_STACK_ALLOC(ptr, len) \

subsys/logging/Kconfig.misc

@@ -74,4 +74,11 @@ config LOG_MEM_UTILIZATION
 config LOG_DICTIONARY_DB
 	bool
 
+config LOG_MSG_APPEND_RO_STRING_LOC
+	bool
+	help
+	  Enable this option to force log messages to always append location of
+	  read-only string arguments in the package. This should be selected by
+	  backends if required.
+
 endmenu