g2-common: init: Define TCP buffer sizes

Define TCP buffer sizes for Wi-Fi, HSPA, HSPA+, and LTE

Change-Id: I81d3b08d3397cfbcbc25954367f341bb95be63eb
g2: init: Fix storage mounting

-Mount /system earlier
-Fix /sdcard/0/0/0/0/0/0/0/0... problem
-Fix run-parts permission denied

Change-Id: I919d2b3d3830d6b5df235cf79b01555d33a7cd82
g2: Build libxml2 and change partition sizes

-Build libxml2 since we're no longer using a prebuilt libxml
-Change partiton sizes (doesn't affect anything, but whatever)

Change-Id: Ia0fe3b7206101f61cf96dea1c244912be67ca693