[FAB-10783] Fix wrong pkg/lib name in devenv.rst

On fabric project, docs/source/dev-setup/devenv.rst has several typos.

Wrong: libtdhl-dev
Correct: libltdl-dev

Wrong: libtdl.h
Correct: ltdl.h

Change-Id: I833af839b47b09d84d9c8f4ca05ac98714378b2c
Signed-off-by: Daisuke IIZUKA <daisuke.iizuka.ag@hitachi.com>

Author: Daisuke IIZUKA

docs/source/dev-setup/devenv.rst

@@ -186,8 +186,8 @@ download the missing package at the following address:
 http://www.microsoft.com/en-us/download/details.aspx?id=8328
 
 **NOTE:** The inclusion of the miekg/pkcs11 package introduces
-an external dependency on the libtdl.h header file during
-a build of fabric. Please ensure your libtool and libtdhl-dev packages
+an external dependency on the ltdl.h header file during
+a build of fabric. Please ensure your libtool and libltdl-dev packages
 are installed. Otherwise, you may get a ltdl.h header missing error.
 You can download the missing package by command:
 ``sudo apt-get install -y build-essential git make curl unzip g++ libtool``.