[DIFF] 5.3 rpi/libpng16.pc: redundant libz

[John Howard]

~/development/rtems/5.3/arm-rtems5/raspberrypi/lib/pkgconfig/libpng16.pc
@@ -8,5 +8,5 @@
Version: 1.6.37
Requires: zlib
Libs: -L${libdir} -lpng16
-Libs.private: -lz -lbsd -lm -lz -lrtemsdefaultconfig
+Libs.private: -lbsd -lm -lz -lrtemsdefaultconfig
Cflags: -I${includedir}