dfu:core: Find DFU alt setting number by passing its name

New function - dfu_get_alt() - has been added to dfu core. If present, it
returns alt setting's number corresponding to passed name.
Signed-off-by: NLukasz Majewski <l.majewski@samsung.com>

drivers/dfu/dfu.c

@@ -440,3 +440,15 @@ struct dfu_entity *dfu_get_entity(int alt)
 
 	return NULL;
 }
+
+int dfu_get_alt(char *name)
+{
+	struct dfu_entity *dfu;
+
+	list_for_each_entry(dfu, &dfu_list, list) {
+		if (!strncmp(dfu->name, name, strlen(dfu->name)))
+			return dfu->alt;
+	}
+
+	return -ENODEV;
+}

include/dfu.h

@@ -126,6 +126,7 @@ const char *dfu_get_layout(enum dfu_layout l);
 struct dfu_entity *dfu_get_entity(int alt);
 char *dfu_extract_token(char** e, int *n);
 void dfu_trigger_reset(void);
+int dfu_get_alt(char *name);
 bool dfu_reset(void);
 int dfu_init_env_entities(char *interface, int dev);