fixup/test compiler warnings

usb/device/dev_hid_composite/dev_hid_composite.c

@@ -134,7 +134,7 @@ void hid_task(void) {
         static bool has_key = false;
 
         static bool toggle = false;
-        if (toggle = !toggle) {
+        if ((toggle = !toggle)) {
             uint8_t keycode[6] = {0};
             keycode[0] = HID_KEY_A;
 

usb/device/dev_lowlevel/dev_lowlevel.c

@@ -113,7 +113,7 @@ struct usb_endpoint_configuration *usb_get_endpoint_configuration(uint8_t addr)
  */
 uint8_t usb_prepare_string_descriptor(const unsigned char *str) {
     // 2 for bLength + bDescriptorType + strlen * 2 because string is unicode. i.e. other byte will be 0
-    uint8_t bLength = 2 + (strlen(str) * 2);
+    uint8_t bLength = 2 + (strlen((const char *)str) * 2);
     static const uint8_t bDescriptorType = 0x03;
 
     volatile uint8_t *buf = &ep0_buf[0];

usb/device/dev_lowlevel/dev_lowlevel.h

@@ -129,8 +129,8 @@ static const unsigned char lang_descriptor[] = {
 };
 
 static const unsigned char *descriptor_strings[] = {
-        "Raspberry Pi",    // Vendor
-        "Pico Test Device" // Product
+        (unsigned char *) "Raspberry Pi",    // Vendor
+        (unsigned char *) "Pico Test Device" // Product
 };
 
 #endif