gnu: libftdi: Update to 1.5.

* gnu/packages/patches/libftdi-fix-paths-when-FTDIPP-set.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/libftdi.scm (libftdi): Update to 1.5.
[source]: Apply patch.
[arguments]<#:configure-flags>: Add "-DFTDIPP", "-DPYTHON_BINDINGS".

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu/packages/patches/libftdi-fix-paths-when-FTDIPP-set.patch

@@ -0,0 +1,39 @@
+commit cdb28383402d248dbc6062f4391b038375c52385
+Author: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+Date:   Fri Jul 17 21:25:03 2020 +0200
+
+    CMakeLists.txt: fix paths when FTDIPP is set
+    
+    Use the same project name (i.e. libftdi1 and not libftdipp1) when FTDIPP
+    is enabled as suggested by Aurelien Jarno in
+    http://developer.intra2net.com/mailarchive/html/libftdi/2020/msg00044.html
+    
+    Without this change, the libftdi1.pc config file defines the include
+    path as /usr/local/include/libftdipp1 while the ftdi.h file is actually
+    installed in /usr/local/include/libftdi1
+    
+    This is an issue for example for libsigrok which will fail on:
+    
+    In file included from src/hardware/asix-sigma/protocol.c:27:
+    src/hardware/asix-sigma/protocol.h:28:10: fatal error: ftdi.h: No such file or directory
+       28 | #include <ftdi.h>
+          |          ^~~~~~~~
+    
+    Fixes:
+     - http://autobuild.buildroot.org/results/1427f44e36752c337791597fab47a1889552a2fe
+    
+    Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 5aecafc..3b0b87c 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -136,7 +136,7 @@ endif ()
+ 
+ add_subdirectory(src)
+ if ( FTDIPP )
+-  project(libftdipp1 C CXX)
++  project(libftdi1 C CXX)
+   add_subdirectory(ftdipp)
+ endif ()
+ if ( PYTHON_BINDINGS )