avr-gcc: revision bump

Closes #219.

Signed-off-by: osxCrossTestBot <[email protected]>

Author: ladislas

Diff for: Formula/avr-gcc.rb

@@ -5,6 +5,7 @@ class AvrGcc < Formula
   url "https://ftp.gnu.org/gnu/gcc/gcc-9.3.0/gcc-9.3.0.tar.xz"
   mirror "https://ftpmirror.gnu.org/gcc/gcc-9.3.0/gcc-9.3.0.tar.xz"
   sha256 "71e197867611f6054aa1119b13a0c0abac12834765fe2d81f35ac57f84f742d1"
+  revision 1
 
   bottle do
     root_url "https://github.com/osx-cross/homebrew-avr/releases/download/avr-gcc-9.3.0"