Shaders: fix copypaste errors in Phong setter docs.

doc/changelog.dox

@@ -550,6 +550,7 @@ See also:
 -   Added a note about MinGW GCC and Clang ABI incompatibility to
     @ref platforms-windows "Windows platform docs" (see [mosra/magnum#227](https://github.com/mosra/magnum/issues/227) and
     [mosra/magnum#439](https://github.com/mosra/magnum/issues/439))
+-   Various documentation fixes (see [mosra/magnum#492](https://github.com/mosra/magnum/issues/492))
 
 @section changelog-2020-06 2020.06
 

src/Magnum/Shaders/Phong.h

@@ -917,7 +917,7 @@ class MAGNUM_SHADERS_EXPORT Phong: public GL::AbstractShaderProgram {
         #endif
 
         /**
-         * @brief Set position for given light
+         * @brief Set color for given light
          * @return Reference to self (for method chaining)
          * @m_since_latest
          *
@@ -967,7 +967,7 @@ class MAGNUM_SHADERS_EXPORT Phong: public GL::AbstractShaderProgram {
         Phong& setLightSpecularColors(std::initializer_list<Magnum::Color3> colors);
 
         /**
-         * @brief Set position for given light
+         * @brief Set specular color for given light
          * @return Reference to self (for method chaining)
          * @m_since_latest
          *