[gdb/testsuite] Unsupport gdb.rust for remote host
With test-case gdb.rust/watch.exp and remote host I run into:
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Executing on host: gcc watch.rs -g -lm -o watch (timeout = 300)
...
ld:watch.rs: file format not recognized; treating as linker script
ld:watch.rs:1: syntax error
...
UNTESTED: gdb.rust/watch.exp: failed to prepare
...
The problem is that find_rustc returns "" for remote host, so we fall back to gcc, which fails.
Fix this by returning 0 in allow_rust_tests for remote host.
Tested on x86_64-linux.
1 file changed
