Hard code library loading

Shortcut the search for the libraries in case the built in
find_library is broken.

As buildroot does not ship any of the external programs that the core
procedure use to find libraries use the canonical name of the shared
object and load it.

In this case this affects loading libftdi and libusb.

This should be reliable as we specify said libs as dependencies of
this package.

Signed-off-by: Christian Kellermann <christian.kellermann@solectrix.de>

---
diff -purN pylibftdi-0.15.0.orig/pylibftdi/driver.py pylibftdi-0.15.0/pylibftdi/driver.py
--- pylibftdi-0.15.0.orig/pylibftdi/driver.py	2015-04-26 22:41:39.000000000 +0200
+++ pylibftdi-0.15.0/pylibftdi/driver.py	2017-02-27 13:08:56.502958000 +0100
@@ -121,8 +121,8 @@ class Driver(object):
                     lib = getattr(cdll, lib_path)
                     break
         if lib is None:
-            raise LibraryMissingError('{} library not found (search: {})'.format(
-                name, search_list))
+            return cdll.LoadLibrary(name + '.so')
+
         return lib
 
     @property