lp8727_charger: Some minor fixes for the header

Pointer coding style changes
: add space between return type and function pointer
  ex) u8(*get_batt_present) (void)
   -> u8 (*get_batt_present) (void)

Signed-off-by: Woogyom Kim <milo.kim@ti.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>