librsvg @2.40.20: patch fails

[ryandesign (Ryan Carsten Schmidt)]

$ sudo port patch librsvg
--->  Computing dependencies for librsvg
--->  Fetching distfiles for librsvg
--->  Verifying checksums for librsvg
--->  Extracting librsvg
--->  Applying patches to librsvg
Error: Failed to patch librsvg: command execution failed
Error: See /opt/local/var/macports/logs/_Users_rschmidt_macports_macports-ports-svn-trunk_graphics_librsvg/librsvg/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets to report a bug.
Error: Processing of port librsvg failed

Probably the changes bcd0bba54c18b9c504e185d9f3e168b1bb54e5b7/macports-ports should have been restricted so that they did not affect the legacy pre-rust version offered to Lion and earlier.

[dbevans (David B. Evans)]

In e168e67ec12b5e52a101280df3b6b8aaca10292c/macports-ports:

librsvg: don't apply cargo changes to pre-cargo build

Fixes #56191