* use PICO_DISABLE_SHARED_IRQ_HANDLERS exclusively as config for no shared handler support (rather than also PICO_MAX_SHARED_IRQ_HANDLERS == 0)
additionally make irq_add_shared_irq_handler() call irq_set_exclusive_handler() so that single usage of an IRQ still works
* Comment typo
Co-authored-by: Luke Wren <wren6991@gmail.com>
In C, func() is a function taking an unspecified number of arguments,
vs func(void) a function taking no arguments. In C++ both forms indicate
"no arguments."
Update these headers to use the (void) form, which is correct in both
languages and avoids complaints when -Wstrict-prototypes is specified.
