Fix warnings
../src/libslic3r/Emboss.cpp:135:24: warning: comparison of integer expressions of different signedness: 'int' and 'const unsigned int' [-Wsign-compare]
../src/libslic3r/Emboss.cpp:653:20: warning: comparison of integer expressions of different signedness: 'int' and 'unsigned int' [-Wsign-compare]
../src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp:2057:12: warning: unused variable 'count_icons' [-Wunused-variable]
../src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp:2058:12: warning: unused variable 'count_states' [-Wunused-variable]