Change peak_refresh_rate value stats reporting

peak_refresh_rate setting could be saved in settings as "Infinity". This setting is for the state when system has no limits of display refresh rate. "Infinity" also allow to share the setting between devices with different max refresh rate limit. After this change SETTING_SNAPSHOT atom will not send "inf" value for this setting. Instead, the atom will have the max refresh rate of all the built-in/physical displays on the device.

Test: previz 10080
Test: Manual tests with different Displays (not built-in, but HDMI, Virtual)
Test:  Manual tests with devices that have different amount of built-in displays
Flag: EXEMPT bugfix
Bug: 339667489
Change-Id: Ibc9c4dfab90efa1cccafbfe78567b902cb630df4

Change-Id: I79f5326335a1d5905457028e75ab118b2af79f2e