Generate USB Strings from apps/*/usb_strings.txt files at compile time
This way we can skip the manually-crafted USB string definitions in the
dfu_desc.c and usb.c files.
diff --git a/firmware/apps/cardem/usb_strings.txt b/firmware/apps/cardem/usb_strings.txt
new file mode 100644
index 0000000..a9c3a8e
--- /dev/null
+++ b/firmware/apps/cardem/usb_strings.txt
@@ -0,0 +1,8 @@
+sysmocom - s.f.m.c. GmbH
+SIMtrace 2 compatible device
+SIMtrace Sniffer
+SIMtrace CCID
+SIMtrace Phone
+SIMtrace MITM
+CardEmulator USIM1
+CardEmulator USIM2