Revert "Fix build on Alpine Linux. issues 150, 319, 344."

This reverts commit 877d1c7.

Author: wb2osz

external/misc/CMakeLists.txt

@@ -32,15 +32,9 @@ if(LINUX)
       )
   endif()
 
-  # add_library doesn't like to get an empty source file list.
-
-  if($misc_SOURCES)
-    add_library(misc STATIC
-      ${misc_SOURCES}
-      )
-  else()
-    set(MISC_LIBRARIES "" CACHE INTERNAL "")
-  endif()
+  add_library(misc STATIC
+    ${misc_SOURCES}
+    )
 
 elseif(WIN32 OR CYGWIN) # windows