USBHostMSD: Implement BlockDevice get_type()

This makes it possible to create instances of USBHostMSD class.

Author: desowin

features/unsupported/USBHost/USBHostMSD/USBHostMSD.cpp

@@ -403,4 +403,9 @@ bd_size_t USBHostMSD::size() const
     USB_DBG("FILESYSTEM: size ");
     return (disk_init ? (bd_size_t)blockSize : 0);
 }
+
+const char *USBHostMSD::get_type() const
+{
+    return "USBMSD";
+}
 #endif

features/unsupported/USBHost/USBHostMSD/USBHostMSD.h

@@ -63,6 +63,7 @@ class USBHostMSD : public IUSBEnumerator, public BlockDevice
     virtual bd_size_t get_program_size() const;
     virtual bd_size_t get_erase_size() const;
     virtual bd_size_t size() const;
+    virtual const char *get_type() const;