Auto merge of #4743 - str4d:cargo-vendor-cleanups, r=str4d

depends: Remove cargo-checksum.sh

Now that we are using `cargo vendor`, the checksum files are computed
automatically.

depends/cargo-checksum.sh

@@ -1,13 +0,0 @@
-echo "{\"files\":{$(
-find . -type f |  	# Get list of file paths
-grep -v $1 |		# Exclude Makefile hashes
-grep -v '[.]stamp_' |	# Exclude Makefile stamps
-sed 's|^[.]/||' |	# Remove leading ./
-sort |			# Sort (for uniformity)
-xargs $2 |		# Get SHA256 hashes (assumes standard 'H(A) A' format)
-awk -v OFS='":"' '{print $2, $1}' |	#   'H(A) A'  ->  'A":"H(A)'
-sed 's|^|"|' |				#  'A":"H(A)' -> '"A":"H(A)'
-sed 's|$|"|' |				# '"A":"H(A)' -> '"A":"H(A)"'
-tr '\n' ',' |		# Concatenate lines with commas
-sed 's|,$||'		# Remove any trailing comma (to fit JSON spec)
-)},\"package\":$3}" > .cargo-checksum.json