backlight: qcom-spmi-wled: Change the default FSC for WLED5 to 25 mA

As per the hardware recommendation, change the default setting
for full scale current for WLED5 peripheral to 25 mA.

Change-Id: Ibad2cd4ade504cc6d361e71e5263c09806365649
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>