Declare the 'rdata' argument for dns_rdata_tostruct() to be const

(cherry picked from commit abb2fd10)
7 jobs for 341-constify-dns_rdata_tostruct-v9_11 in 9 minutes and 9 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Precheck
passed #18940
amd64 docker linux
precheck:debian:sid:amd64

00:00:12

 
  Build
passed #18941
amd64 docker linux
build:debian:sid:amd64

00:03:01

passed #18942
i386 docker linux
build:debian:sid:i386

00:03:15

 
  Test
passed #18945
amd64 docker linux
systemtest:debian:sid:amd64

00:04:54

passed #18946
i386 docker linux
systemtest:debian:sid:i386

00:05:13

passed #18943
amd64 docker linux
unittest:debian:sid:amd64

00:00:59

passed #18944
i386 docker linux
unittest:debian:sid:i386

00:00:54