cmake: update optimization filter

cmake/OpenCVCompilerOptimizations.cmake

@@ -24,7 +24,7 @@
 # CPU_BASELINE_FINAL=<list> - final list of enabled compiler optimizations
 # CPU_DISPATCH_FINAL=<list> - final list of dispatched optimizations
 #
-# CPU_DISPATCH_FLAGS_${opt} - flags for source files compiled separately (_opt_avx2.cpp)
+# CPU_DISPATCH_FLAGS_${opt} - flags for source files compiled separately (<name>.avx2.cpp)
 
 set(CPU_ALL_OPTIMIZATIONS "SSE;SSE2;SSE3;SSSE3;SSE4_1;SSE4_2;POPCNT;AVX;FP16;AVX2;FMA3") # without AVX512
 list(APPEND CPU_ALL_OPTIMIZATIONS NEON VFPV3 FP16)
@@ -537,7 +537,7 @@ macro(ocv_compiler_optimization_process_sources SOURCES_VAR_NAME LIBS_VAR_NAME T
   foreach(fname ${${SOURCES_VAR_NAME}})
     string(TOLOWER "${fname}" fname_LOWER)
     get_filename_component(fname_LOWER "${fname_LOWER}" NAME)
-    if(fname_LOWER MATCHES "\\.(.*)\\.cpp$")
+    if(fname_LOWER MATCHES ".+\\.([^\\.]*)\\.cpp$")
       string(TOUPPER "${CMAKE_MATCH_1}" OPT_)
       if(OPT_ MATCHES "(CUDA.*|DISPATCH.*|OCL)") # don't touch files like filename.cuda.cpp
         list(APPEND __result "${fname}")