fbt: 'target' field for apps; lib debugging support (#1995)

* fbt: added 'target' field to application manifest
* fbt: earlier pagination setup for gdb
* fbt: added LIB_DEBUG flag
* fbt: sdk: added SDK_MAP_FILE_SUBST

scripts/fbt_tools/fbt_debugopts.py

@@ -41,12 +41,12 @@ def generate(env, **kw):
             "|openocd -c 'gdb_port pipe; log_output ${FBT_DEBUG_DIR}/openocd.log' ${[SINGLEQUOTEFUNC(OPENOCD_OPTS)]}"
         ],
         GDBOPTS_BASE=[
+            "-ex",
+            "set pagination off",
             "-ex",
             "target extended-remote ${GDBREMOTE}",
             "-ex",
             "set confirm off",
-            "-ex",
-            "set pagination off",
         ],
         GDBOPTS_BLACKMAGIC=[
             "-ex",