mmc: tmio: give callback a generic name

mmc: tmio: give callback a generic name

check_scc_error() is too Renesas specific. Let's just call it
check_retune() to make it also easier understandable what it does.
Only a rename, no functional change.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20200129203709.30493-4-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>