Fix several configuration varaibles that were defined in multiple Kconfig files and/or lacked any scoping and the naming.
Squashed commit of the following:
lpc17, pic32mx, pic32mz: Fix duplicated, improperly scoped configuration variable names: CONFIG_PHY_SPEED100 and CONFIG_PHY_AUTONEG.
lpc17, pic32mx, pic32mz: Fix another duplicated configuration variable name: CONFIG_PHY_FDUPLEX.
lpc17: Fix naming scope: CONFIG_NET_HASH -> CONFIG_LPC17_ETH_HASH.
lpc17: Fix naming scope: CONFIG_NET_WOL -> CONFIG_LPC17_ETH_WOL.
lpc17, pic32mx, pic32mz: Fix naming scope: CONFIG_NET_ -> CONFIG_LPC17_ETH_PRIORITY.
lpc17, pic32mx, pic32mz: Fix another duplicated configuration variable name: CONFIG_NET_NTXDESC and CONFIG_NET_NRXDESC.
lpc17: Fix naming scope: CONFIG_NET_EMACRAM_SIZE -> CONFIG_LPC17_EMACRAM_SIZE.