[devel] Fix a spelling typo in the contrib/pngminim makefiles
diff --git a/contrib/pngminim/decoder/makefile b/contrib/pngminim/decoder/makefile
index 9e6a0e3..ca29d44 100644
--- a/contrib/pngminim/decoder/makefile
+++ b/contrib/pngminim/decoder/makefile
@@ -49,7 +49,7 @@
pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \
pngset$(C) pngtrans$(C)
-# Standard headres
+# Standard headers
PNGH =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
# Machine generated headers
diff --git a/contrib/pngminim/encoder/makefile b/contrib/pngminim/encoder/makefile
index 6574308..3a6a192 100644
--- a/contrib/pngminim/encoder/makefile
+++ b/contrib/pngminim/encoder/makefile
@@ -49,7 +49,7 @@
pngset$(C) pngtrans$(C) pngwio$(C) pngwrite$(C) \
pngwtran$(C) pngwutil$(C)
-# Standard headres
+# Standard headers
PNGH =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
# Machine generated headers
diff --git a/contrib/pngminim/preader/makefile b/contrib/pngminim/preader/makefile
index a47efee..b36fbba 100644
--- a/contrib/pngminim/preader/makefile
+++ b/contrib/pngminim/preader/makefile
@@ -65,7 +65,7 @@
pngpread$(C) pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \
pngset$(C) pngtrans$(C)
-# Standard headres
+# Standard headers
PNGH =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
# Machine generated headers
