multiarch: Set CMAKE_LIBRARY_ARCHITECTURE_REGEX for Linux|Hurd|kFreeBSD

* Fix linux CMAKE_LIBRARY_ARCHITECTURE_REGEX to support armel-linux-gnueabi.
* Add CMAKE_LIBRARY_ARCHITECTURE_REGEX on kFreeBSD.
* Add CMAKE_LIBRARY_ARCHITECTURE_REGEX on GNU (Hurd).

Also regex is improved to support quadlets.  Even if I have not seen this
in the wild yet, reportedly they are possible.

Modules/Platform/GNU.cmake

@@ -8,4 +8,6 @@ SET(CMAKE_SHARED_LIBRARY_RPATH_LINK_C_FLAG "-Wl,-rpath-link,")
 SET(CMAKE_SHARED_LIBRARY_SONAME_C_FLAG "-Wl,-soname,")
 SET(CMAKE_EXE_EXPORTS_C_FLAG "-Wl,--export-dynamic")
 
+SET(CMAKE_LIBRARY_ARCHITECTURE_REGEX "[a-z0-9_]+(-[a-z0-9_]+)?-gnu[a-z0-9_]*")
+
 INCLUDE(Platform/UnixPaths)

Modules/Platform/Linux.cmake

@@ -46,7 +46,7 @@ ELSE(DEFINED CMAKE_INSTALL_SO_NO_EXE)
 ENDIF(DEFINED CMAKE_INSTALL_SO_NO_EXE)
 
 # Match multiarch library directory names.
-SET(CMAKE_LIBRARY_ARCHITECTURE_REGEX "[a-z0-9_]+-linux-gnu")
+SET(CMAKE_LIBRARY_ARCHITECTURE_REGEX "[a-z0-9_]+(-[a-z0-9_]+)?-linux-gnu[a-z0-9_]*")
 
 INCLUDE(Platform/UnixPaths)
 

Modules/Platform/kFreeBSD.cmake

@@ -1,2 +1,4 @@
 # kFreeBSD looks just like Linux.
 INCLUDE(Platform/Linux)
+
+SET(CMAKE_LIBRARY_ARCHITECTURE_REGEX "[a-z0-9_]+(-[a-z0-9_]+)?-kfreebsd-gnu[a-z0-9_]*")