gpioleds: fallack to label property

[Klemens Nanni]

Some device trees such as on my Raspberry Pi 4b use the deprecated
"label" property rather than "function".

Fall back to it such that LEDs won't be skipped:

        -gpioleds0 at mainbus0: no LEDs
        +gpioleds0 at mainbus0: "led0", "led1"

OK?

Index: gpioleds.c
===================================================================
RCS file: /cvs/src/sys/dev/fdt/gpioleds.c,v
retrieving revision 1.1
diff -u -p -r1.1 gpioleds.c
--- gpioleds.c  25 Sep 2021 10:43:24 -0000      1.1
+++ gpioleds.c  3 Nov 2021 18:41:44 -0000
@@ -60,15 +60,20 @@ gpioleds_attach(struct device *parent, s
        struct fdt_attach_args  *faa = aux;
        uint32_t                *led_pin;
        char                    *function, *default_state;
+       char                    *function_prop = "function";
        int                      function_len, default_state_len, gpios_len;
        int                      node, leds = 0;
 
        pinctrl_byname(faa->fa_node, "default");
 
        for (node = OF_child(faa->fa_node); node; node = OF_peer(node)) {
-               function_len = OF_getproplen(node, "function");
-               if (function_len <= 0)
-                       continue;
+               function_len = OF_getproplen(node, function_prop);
+               if (function_len <= 0) {
+                       function_prop = "label";
+                       function_len = OF_getproplen(node, function_prop);
+                       if (function_len <= 0)
+                               continue;
+               }
                default_state_len = OF_getproplen(node, "default-state");
                if (default_state_len <= 0)
                        continue;
@@ -77,7 +82,7 @@ gpioleds_attach(struct device *parent, s
                        continue;
 
                function = malloc(function_len, M_TEMP, M_WAITOK);
-               OF_getprop(node, "function", function, function_len);
+               OF_getprop(node, function_prop, function, function_len);
                default_state = malloc(default_state_len, M_TEMP, M_WAITOK);
                OF_getprop(node, "default-state", default_state, 
default_state_len);
                led_pin = malloc(gpios_len, M_TEMP, M_WAITOK);
@@ -94,9 +99,7 @@ gpioleds_attach(struct device *parent, s
                free(led_pin, M_TEMP, gpios_len);
        }
 
-       if (leds == 0) {
-               printf(": no LEDs\n");
-               return;
-       }
+       if (leds == 0)
+               printf(": no LEDs");
        printf("\n");
 }