deps: the pin advances to the reviewed libavr, and the clock example is 6 B smaller

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/CMakeLists.txt

@@ -3,7 +3,7 @@ libavr_format_test()
 # The example's size is stated in the README, per chip, and a library advance
 # that moves it silently is what this catches.
 if(LIBAVR_MCU STREQUAL "atmega328p")
-	libavr_size_claim_test(clock 1468)
+	libavr_size_claim_test(clock 1462)
 elseif(LIBAVR_MCU STREQUAL "attiny85")
 	libavr_size_claim_test(clock 1256)
 endif()