regulator: dbx500: Remove unused debugfs goto label

regulator: dbx500: Remove unused debugfs goto label

The following build warning is seen after commit 8bdaa43808b7 ("regulator:
dbx500: no need to check return value of debugfs_create functions"):

drivers/regulator/dbx500-prcmu.c:144:1: warning: label 'exit_no_debugfs' defined but not used [-Wunused-label]

Remove the unused label and its associated error message.

Fixes: 8bdaa43808b7 ("regulator: dbx500: no need to check return value of debugfs_create functions")
Reported-by: Olof's autobuilder <build@lixom.net>
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20200821144823.13404-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>