Fix test-case gdb.cp/cp-relocate.exp for remote host using
gdb_remote_download.
Tested on x86_64-linux.
# Now start a clean GDB, for add-symbol-file tests.
clean_restart
-gdb_test "add-symbol-file ${binfile} 0 -s ${func1_sec} 0x10000 -s ${func2_sec} 0x20000" \
+set host_binfile [gdb_remote_download host $binfile]
+
+gdb_test "add-symbol-file $host_binfile 0 -s ${func1_sec} 0x10000 -s ${func2_sec} 0x20000" \
"Reading symbols from .*${testfile}\\.o\\.\\.\\.(|\r\nUsing host libthread_db library .*libthread_db.so.*\\.)" \
"add-symbol-file ${testfile}.o" \
"add symbol table from file \".*${testfile}\\.o\" at.*\\(y or n\\) " \