Added optional support for Sparkfun SiGe GN3S USB GPS RF sampler:

- Added a pre-compiled custom GN3S firmware.
- Added a fully-compliant GNU Radio source block for GN3S USB dongle. It can be used also from GNU Radio companion and from Python applications.
- Added a new GN3S_Signal_Source block. It is possible to disable the GN3S signal source compilation. See README.

git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@217 64b25241-fba3-4117-9849-534c7e92360d

drivers/gr-gn3s/cmake/Modules/GrPlatform.cmake

@@ -0,0 +1,46 @@
+# Copyright 2011 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+
+if(DEFINED __INCLUDED_GR_PLATFORM_CMAKE)
+    return()
+endif()
+set(__INCLUDED_GR_PLATFORM_CMAKE TRUE)
+
+########################################################################
+# Setup additional defines for OS types
+########################################################################
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+    set(LINUX TRUE)
+endif()
+
+if(LINUX AND EXISTS "/etc/debian_version")
+    set(DEBIAN TRUE)
+endif()
+
+if(LINUX AND EXISTS "/etc/redhat-release")
+    set(REDHAT TRUE)
+endif()
+
+########################################################################
+# when the library suffix should be 64 (applies to redhat linux family)
+########################################################################
+if(NOT DEFINED LIB_SUFFIX AND REDHAT AND CMAKE_SYSTEM_PROCESSOR MATCHES "64$")
+    set(LIB_SUFFIX 64)
+endif()
+set(LIB_SUFFIX ${LIB_SUFFIX} CACHE STRING "lib directory suffix")