Dfu-programmer cannot cannot find libusb. This patch fixes that.

diff --git a/src/dfu-device.h b/src/dfu-device.h
index bbdfa99..31af0e8 100644
--- a/src/dfu-device.h
+++ b/src/dfu-device.h
@@ -6,7 +6,7 @@
 #endif
 #include <stdint.h>
 #ifdef HAVE_LIBUSB_1_0
-#include <libusb.h>
+#include <libusb-1.0/libusb.h>
 #else
 #include <usb.h>
 #endif

diff --git a/src/main.c b/src/main.c
index ef2aa16..dcc3636 100644
--- a/src/main.c
+++ b/src/main.c
@@ -24,7 +24,7 @@
 #include <stdio.h>
 #include <string.h>
 #ifdef HAVE_LIBUSB_1_0
-#include <libusb.h>
+#include <libusb-1.0/libusb.h>
 #else
 #include <usb.h>
 #endif

diff --git a/src/dfu.c b/src/dfu.c
index 7dbcc57..952e896 100644
--- a/src/dfu.c
+++ b/src/dfu.c
@@ -27,7 +27,7 @@
 #include <stdlib.h>
 #include <stddef.h>
 #ifdef HAVE_LIBUSB_1_0
-#include <libusb.h>
+#include <libusb-1.0/libusb.h>
 #else
 #include <usb.h>
 #endif

diff --git a/src/dfu.h b/src/dfu.h
index 2a159e8..63510f2 100644
--- a/src/dfu.h
+++ b/src/dfu.h
@@ -25,7 +25,7 @@
 # include <config.h>
 #endif
 #ifdef HAVE_LIBUSB_1_0
-#include <libusb.h>
+#include <libusb-1.0/libusb.h>
 #else
 #include <usb.h>
 #endif
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<tr><td><span title='2017-05-08 19:16:13 -0400'>2017-05-08</span></td><td><a href='/guix/commit/gnu/packages/nfs.scm?id=d14b8dbb748c064e0d43506c17c80cad61665510'>gnu: nfs-utils: Adjust indentation.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-05-08 19:16:09 -0400'>2017-05-08</span></td><td><a href='/guix/commit/gnu/packages/nfs.scm?id=a472f0d0752366a702515c28b1184b564fabf366'>gnu: nfs-utils: Update to 2.1.1.</a><span class='msg-avail'>...</span></td><td>Leo Famulari</td></tr>
<tr><td><span title='2017-01-19 00:11:15 +0100'>2017-01-19</span></td><td><a href='/guix/commit/gnu/packages/nfs.scm?id=89e34644d94860fafc053b759961ba8b55a6c77c'>gnu: Move Kerberos implemetations to (gnu packages kerberos).</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-09-12 18:17:57 +0200'>2016-09-12</span></td><td><a href='/guix/commit/gnu/packages/nfs.scm?id=e9aba1ea338d9e311c005ee294992297f19b8ca5'>gnu: Add nfs-utils</a><span class='msg-avail'>...</span></td><td>John Darrington</td></tr>