pcidev: Move pci_card_find() from internal to canonical place

Also rename to `pcidev_card_find()` in fitting with pcidev.c helpers.

Tested: ```sudo ./flashrom -p internal -r /tmp/bios
<snip>
Found Programmer flash chip "Opaque flash chip" (16384 kB, Programmer-specific) mapped at physical address 0x0000000000000000.
Reading flash... done.
```

Change-Id: I026bfbecba114411728d4ad1ed8969b469fa7d2d
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/59279
Original-Reviewed-by: Thomas Heijligen <src@posteo.de>
Original-Reviewed-by: Nikolai Artemiev <nartemiev@google.com>
Original-Reviewed-by: Anastasia Klimchuk <aklm@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/72309
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
4 files changed