mfd: ab8500-sysctrl: Fix Constify, printk => pr_info and formatting issues

WARNING: char * array declaration might be better as static const
+       static char *pss[] = {"ab8500_ac", "pm2301", "ab8500_usb"};

WARNING: Prefer [subsystem eg: netdev]_info([subsystem]dev, ... then dev_info(dev, ... then
 pr_info(...  to printk(KERN_INFO ...
+                       printk(KERN_INFO

WARNING: quoted string split across lines
+                              "Charger \"%s\" is connected with known battery."
+                              " Rebooting.\n",

WARNING: quoted string split across lines
+                                       "unable to set sysClkReq%dRfClkBuf: "
+                                       "%d\n", j + 1, ret);

total: 0 errors, 4 warnings, 199 lines checked

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>