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='2021-02-22 12:07:45 +0100'>2021-02-22</span></td><td><a href='/guix/commit/tests/guix-lint.sh?id=9a38bed2cf32e9462badfa43e74cdd4580e804fc'>packages: 'package-field-location' handles 'search-path' returning #f.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/46390&gt;.
Reported by zimoun &lt;zimon.toutoune@gmail.com&gt;.

This is similar to the fix in d10474c38d58bdc676e64336769dc2e00cdfa8ed.

* guix/packages.scm (package-field-location): Handle FILE not in %LOAD-PATH.
* tests/guix-lint.sh: Add test.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-09-28 21:06:36 -0500'>2020-09-28</span></td><td><a href='/guix/commit/tests/guix-lint.sh?id=d8934360d2453a403b5433e71d09188e4ed23b57'>tests: Simplify shell exit status negation;</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-lint.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh: Use the shell '!' keyword to negate command exit status
in place of 'if ...; then false; else true; fi'
</span></span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2020-08-23 23:05:16 +0200'>2020-08-23</span></td><td><a href='/guix/commit/tests/guix-lint.sh?id=d10474c38d58bdc676e64336769dc2e00cdfa8ed'>lint: formatting: Gracefully handle relative file names.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/42543&gt;.
Reported by Jack Hill &lt;jackhill@jackhill.us&gt;.

* guix/lint.scm (check-formatting): Always return a list (previously we
would return #f when 'search-path' returns #f).  Check whether
LOCATION's file is a relative file name.  Return a warning if not.
* tests/guix-lint.sh: Add test.
</span></span></td><td>Ludovic Courtès</td></tr>