pinctrl: qcom: spmi-gpio: Fix the GPIO strength mapping

The SPMI based PMICs have the HIGH and LOW GPIO output
strength mappings interchanged, fix them.

Keep the mapping same for older SSBI based PMICs.

CRs-Fixed: 2246473
Change-Id: I4ec78469c436b54642ee67108943c82fba46e1c4
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>