filter_base.hpp: use unsigned long instead of size_t in getParam 2nd parameter

* it was added in:
  25c7d30
  but unfortunately on 32bit systems size_t could be the same as unsigned int already
  defined above and then the build fails with:

| filters/2.0.0-1-r0/git/include/filters/filter_base.hpp:219:8: error: 'bool filters::FilterBase<T>::getParam(const string&, size_t&)' cannot be overloaded with 'bool filters::FilterBase<T>::getParam(const string&, unsigned int&)'
|   219 |   bool getParam(const std::string & name, size_t & value)
|       |        ^~~~~~~~
| filters/2.0.0-1-r0/git/include/filters/filter_base.hpp:201:8: note: previous declaration 'bool filters::FilterBase<T>::getParam(const string&, unsigned int&)'
|   201 |   bool getParam(const std::string & name, unsigned int & value)
|       |        ^~~~~~

Signed-off-by: Martin Jansa <[email protected]>

Author: shr-project

Diff for: include/filters/filter_base.hpp

@@ -212,11 +212,11 @@ class FilterBase
   }
 
   /**
-   * \brief Get a filter parameter as a size_t
+   * \brief Get a filter parameter as an unsigned long
    * \param name The name of the parameter
    * \param value The int to set with the value
    * \return Whether or not the parameter of name/type was set */
-  bool getParam(const std::string & name, size_t & value)
+  bool getParam(const std::string & name, unsigned long & value)
   {
     int signed_value;
     if (!getParam(name, signed_value)) {