avrdude: update to 8.1

cross/avrdude/Portfile

@@ -4,7 +4,7 @@ PortSystem          1.0
 PortGroup           github 1.0
 PortGroup           cmake 1.1
 
-github.setup        avrdudes avrdude 7.3 v
+github.setup        avrdudes avrdude 8.1 v
 
 categories          cross devel
 license             GPL-2+
@@ -20,15 +20,20 @@ long_description    AVRDUDE - AVR Downloader Uploader - is a program for downloa
 
 github.tarball_from archive
 
-checksums           rmd160  f9dd95320eeb45c45ed7c076cfbd6e2517914939 \
-                    sha256  1c61ae67aacf8b8ccae5741f987ba4b0c48d6e320405520352a8eca8c6e2c457 \
-                    size    3260070
+checksums           rmd160  2a5ac8c842e70aaf3e1536480afe0f9aad5038f8 \
+                    sha256  2d3016edd5281ea09627c20b865e605d4f5354fe98f269ce20522a5b910ab399 \
+                    size    6526042
+
+depends_build-append \
+                    port:flex \
+                    port:bison
 
 depends_lib         port:hidapi \
                     port:libelf \
                     port:libftdi1 \
                     port:libserialport \
-                    port:libusb
+                    port:libusb \
+                    port:readline
 
 # Target "cmTC_6e3dd" requires the language dialect "C11"
 compiler.c_standard 2011