i2c: tegra: enable compile testing on all archs

Commit 4a2d5f663dab ("i2c: Enable compile testing for more drivers")
enabled compile testing of the Tegra i2c driver only for architectures
that explicitly provide readsX() and writesX().

This limitation appears to have been too restrictive since the generic
implementation of these primitives added by commit 9ab3a7a0d2b4
("asm-generic/io.h: Implement generic {read,write}s*()") predates the
commit in question.

Allow compile testing of the driver on all architectures.

Cc: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>