Add IAR to the CMakeDetectC(XX)CompilerID.c(pp).in

With the AVR IAR compiler this can't be found, but it works e.g. for the
ARM AVR compiler.

Alex

Modules/CMakeCCompilerId.c.in

@@ -160,10 +160,9 @@
 # define COMPILER_ID "ADSP"
 
 /* IAR Systems compiler for embedded systems.
-   http://www.iar.com
-   Not supported yet by CMake
-#elif defined(__IAR_SYSTEMS_ICC__)
-# define COMPILER_ID "IAR" */
+   http://www.iar.com */
+#elif defined(__IAR_SYSTEMS_ICC__ ) || defined(__IAR_SYSTEMS_ICC)
+# define COMPILER_ID "IAR"
 
 /* sdcc, the small devices C compiler for embedded systems,
    http://sdcc.sourceforge.net  */

Modules/CMakeCXXCompilerId.cpp.in

@@ -161,6 +161,11 @@
 #elif defined(__ADSPBLACKFIN__) || defined(__ADSPTS__) || defined(__ADSP21000__)
 # define COMPILER_ID "ADSP"
 
+/* IAR Systems compiler for embedded systems.
+   http://www.iar.com */
+#elif defined(__IAR_SYSTEMS_ICC__ ) || defined(__IAR_SYSTEMS_ICC)
+# define COMPILER_ID "IAR"
+
 #elif defined(_SGI_COMPILER_VERSION) || defined(_COMPILER_VERSION)
 # define COMPILER_ID "MIPSpro"
 # if defined(_SGI_COMPILER_VERSION)