Fix cmake issue

Signed-off-by: jinge90 <[email protected]>

Author: jinge90

libdevice/cmake/modules/SYCLLibdevice.cmake

@@ -197,8 +197,12 @@ function(add_devicelibs filename)
   endforeach()
 
   foreach(arch IN LISTS devicelib_arch)
-    list(FIND ${ARG_SKIP_ARCHS} "${arch}" skip_idx)
-    if (${skip_idx} EQUAL -1)
+    set(skip_idx -1)
+    set(skip_arch_list ${ARG_SKIP_ARCHS})
+    if (skip_arch_list)
+      list(FIND skip_arch_list ${arch} skip_idx)
+    endif()
+    if (skip_idx EQUAL -1)
       compile_lib(${filename}-${arch}
         FILETYPE bc
         SRC ${ARG_SRC}