Fixes for github issues
This MR contains a bunch of small fixes for issues raised on Github and esp32.com forum:
- vfs doesn't check error code returned by open syscall
- spi_flash doesn't work when built in release mode
- duplicate definition of O_NONBLOCK when combining LwIP socket.h with sys/fcntl.h
- wrong order of creation of standard streams
- `_times_r` returning incorrect values, causing `clock`to return double of the actual time
- driver/gpio.h: comment fix
- wifi event handlers: fix incorrect MAC address printed by logging statements
- move some functions out of IRAM when compiling for bootloader
Please check commit descriptions for links to issues/forum posts and more details.
See merge request !183