asm support: adapt to changes in CMakeDetectCompiler in 2.8.10

This fixes #14210. In 2.8.10 CMakeDetermineCompiler.cmake was
modified (or added), and now the _INIT variable must not
be set to a list anymore, before it worked.

Alex

Modules/CMakeDetermineASM-ATTCompiler.cmake

@@ -15,6 +15,6 @@
 # determine the compiler to use for ASM using AT&T syntax, e.g. GNU as
 
 set(ASM_DIALECT "-ATT")
-set(CMAKE_ASM${ASM_DIALECT}_COMPILER_INIT ${_CMAKE_TOOLCHAIN_PREFIX}gas ${_CMAKE_TOOLCHAIN_PREFIX}as)
+set(CMAKE_ASM${ASM_DIALECT}_COMPILER_LIST ${_CMAKE_TOOLCHAIN_PREFIX}gas ${_CMAKE_TOOLCHAIN_PREFIX}as)
 include(CMakeDetermineASMCompiler)
 set(ASM_DIALECT)

Modules/CMakeDetermineASMCompiler.cmake

@@ -39,8 +39,8 @@ if(NOT CMAKE_ASM${ASM_DIALECT}_COMPILER)
       endif()
     endif()
   else() # some specific assembler "dialect"
-    if(NOT CMAKE_ASM${ASM_DIALECT}_COMPILER_INIT)
-      message(FATAL_ERROR "CMAKE_ASM${ASM_DIALECT}_COMPILER_INIT must be preset !")
+    if(NOT CMAKE_ASM${ASM_DIALECT}_COMPILER_INIT  AND NOT CMAKE_ASM${ASM_DIALECT}_COMPILER_LIST)
+      message(FATAL_ERROR "CMAKE_ASM${ASM_DIALECT}_COMPILER_INIT or CMAKE_ASM${ASM_DIALECT}_COMPILER_LIST must be preset !")
     endif()
   endif()
 

Modules/CMakeDetermineASM_NASMCompiler.cmake

@@ -14,7 +14,7 @@
 
 # Find the nasm assembler. yasm (http://www.tortall.net/projects/yasm/) is nasm compatible
 
-set(CMAKE_ASM_NASM_COMPILER_INIT nasm yasm)
+set(CMAKE_ASM_NASM_COMPILER_LIST nasm yasm)
 
 if(NOT CMAKE_ASM_NASM_COMPILER)
   find_program(CMAKE_ASM_NASM_COMPILER nasm