cmCMakeMinimumRequired: Use unsigned int for version numbers

Source/cmCMakeMinimumRequired.cxx

@@ -63,17 +63,17 @@ bool cmCMakeMinimumRequired
 
 
   // Get the current version number.
-  int current_major = cmVersion::GetMajorVersion();
-  int current_minor = cmVersion::GetMinorVersion();
-  int current_patch = cmVersion::GetPatchVersion();
-  int current_tweak = cmVersion::GetTweakVersion();
+  unsigned int current_major = cmVersion::GetMajorVersion();
+  unsigned int current_minor = cmVersion::GetMinorVersion();
+  unsigned int current_patch = cmVersion::GetPatchVersion();
+  unsigned int current_tweak = cmVersion::GetTweakVersion();
 
   // Parse at least two components of the version number.
   // Use zero for those not specified.
-  int required_major = 0;
-  int required_minor = 0;
-  int required_patch = 0;
-  int required_tweak = 0;
+  unsigned int required_major = 0;
+  unsigned int required_minor = 0;
+  unsigned int required_patch = 0;
+  unsigned int required_tweak = 0;
   if(sscanf(version_string.c_str(), "%u.%u.%u.%u",
             &required_major, &required_minor,
             &required_patch, &required_tweak) < 2)