Update scripts/install_cppcheck.sh for v2.15.0

Remove the setting of CPPFLAGS for cppcheck v2.15.0 as this
upsets the setting of FILESDIR

(cherry picked from commit bc3f0e6)

scripts/install_cppcheck.sh

@@ -132,12 +132,7 @@ fi
             # CFGDIR is needed for cppcheck before 1.86
             make_args="$make_args CFGDIR=$FILESDIR"
             ;;
-        2.8 | 2.9 | 2.1*)
-            # Cppcheck 2.8 removed the dependency on z3
-            # Cppcheck 2.8 added optional support for utilizing Boost
-            make_args="$make_args CPPFLAGS=-DHAVE_BOOST"
-            ;;
-        2.*)
+        2.0 | 2.1 | 2.2 | 2.3 | 2.4 | 2.4.1 | 2.5 | 2.6 | 2.7)
             make_args="$make_args USE_Z3=yes"
             # Check that the Z3 development files appear to be installed
             # before trying to create z3_version.h. Otherwise we may
@@ -149,6 +144,14 @@ fi
                 create_z3_version_h
             fi
             ;;
+        2.8 | 2.9 | 2.10 | 2.11* | 2.12.* | 2.13.* | 2.14.* )
+            # Cppcheck 2.8 removed the dependency on z3
+            # Cppcheck 2.8 added optional support for utilizing Boost
+            make_args="$make_args CPPFLAGS=-DHAVE_BOOST"
+            ;;
+        2.*)
+            # Cppcheck 2.15 doesn't seem to define FILESDIR if CPPFLAGS is set
+            ;;
     esac
 
     # Use all available CPUs