arch/mips/src/mips32: In up_idle, the kludge that was conditionally enabled...

arch/mips/src/mips32:  In up_idle, the kludge that was conditionally enabled if the work queue was enable appears to be needed even when he work queue is not enabled on the PIC32MZ.

arch/mips/src/pic32mz: Fix some typos in debug instrumentation in pic32mz-gpio.c; fix some types releated to UART5 configuration in pic32mz-serial.c.

configs/flipnclick-pic32mz/nsh:  Switch serial console to UART3.  There is some problem with the UART4 RX pin documentation or configuration.