Use -rpath option when linking all the libraries too

Previously this was used only for linking the samples, which ensured
that they found the libraries directly referenced by them, but this
wasn't enough to find the libraries referenced indirectly, via another
library (e.g. wxxml used by wxxrc internally but not necessarily
referenced by the sample using XRC) because DT_RUNPATH is not used in
this case, as documented in Linux ld.so(8).

Ensure that such libraries are found nevertheless by setting runpath
for all the libraries too.

Note that it would probably be more logical to just get rid of
SAMPLES_RPATH_FLAG and use DYLIB_RPATH_FLAG everywhere, but this would
result in a ton of changes, so keep the old variable for now and just
set it to the same value to avoid this and keep the possibility to
change it to a different value if necessary later.

build/bakefiles/common.bkl

@@ -726,6 +726,7 @@ $(TAB)cl /EP /nologo "$(DOLLAR)(InputPath)" > "$(SETUPHDIR)\wx\msw\rcdefs.h"
     <template id="wx_dll_b" template="wx_lib_b">
         <set var="WXDLLNAME">$(wxwin.mkDllName(wxid))</set>
         <if cond="FORMAT=='autoconf'">
+            <ldflags>$(DYLIB_RPATH_FLAG)</ldflags>
             <set var="__dllinstdir">$(DLLDIR)</set>
         </if>
         <dllname>$(WXDLLNAME)</dllname>

build/bakefiles/config.bkl

@@ -415,6 +415,7 @@ compiled .lib files and setup.h under the lib/ toplevel directory.
         <option name="WX_CXXFLAGS"/>
         <option name="WX_LDFLAGS"/>
         <option name="HOST_SUFFIX"/>
+        <option name="DYLIB_RPATH_FLAG"/>
         <option name="DYLIB_RPATH_INSTALL"/>
         <option name="DYLIB_RPATH_POSTLINK"/>
         <option name="SAMPLES_RPATH_FLAG"/>