[region] added test for mixed comp-array

src/plugins/region/tests/region/comp.c

+void f() {
+  struct { int x; int y; int* z; short arr[4]; } s;
+  int a = 1;
+  s.x = a;
+  s.z = &a;
+  s.arr[1] = 0;
+}

src/plugins/region/tests/region/oracle/comp.res.oracle

+[kernel] Parsing comp.c (with preprocessing)
+[region] Analyzing regions
+[region] Function f:
+  R0003: --- s 192b 0..32 [1]: R0004 64..128 [1]: R0007 128..192 [1]: R000b ;
+  R0004: -W- (int) 32b ;
+  R0007: -W- (int *) 64b (*R0001) ;
+  R0001: RW- a (int) 32b ;
+  R000b: --- 64b 0..64 [4]: R000d ;
+  R000d: -W- (short) 16b ;