pinctrl: berlin: fix error return code of berlin_pinctrl_build_state()

When krealloc() fails and pctrl->functions is NULL, no error
return code of berlin_pinctrl_build_state() is assigned.
To fix this bug, ret is assigned with -ENOMEM when pctrl->functions
is NULL.
Signed-off-by: Meng Tang <tangmeng@uniontech.com>
Link: https://lore.kernel.org/r/20220303080206.16463-1-tangmeng@uniontech.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/berlin/berlin.c

@@ -233,6 +233,8 @@ static int berlin_pinctrl_build_state(struct platform_device *pdev)
 	pctrl->functions = krealloc(pctrl->functions,
 				    pctrl->nfunctions * sizeof(*pctrl->functions),
 				    GFP_KERNEL);
+	if (!pctrl->functions)
+		return -ENOMEM;
 
 	/* map functions to theirs groups */
 	for (i = 0; i < pctrl->desc->ngroups; i++) {