Correctly set CMAKE_MODULE_PATH

Since CMAKE_MODULE_PATH can already be set by another project,
we should just append the libhsamkt cmake module directory to it.

Change-Id: I999dc52a2862e4bbff02e0a8e8b39530f4dae2cd
Signed-off-by: Vlad Sytchenko <vladislav.sytchenko@amd.com>

CMakeLists.txt

@@ -60,10 +60,7 @@ if (ROCM_CCACHE_BUILD)
   endif() # if (CCACHE_PROGRAM)
 endif() # if (ROCM_CCACHE_BUILD)
 
-## Set default module path if not already set
-if ( NOT DEFINED CMAKE_MODULE_PATH )
-    set ( CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake_modules/" )
-endif ()
+list( APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake_modules" )
 
 ## Include common cmake modules
 include ( utils )