1. Make sure Pico SDK libraries have the correct dependencies on other SDK libraries
2. Pico SDK libraries all have _headers variants to include the headers. This may facilitate building user STATIC libraries without
pulling in SDK code, though care will still need to be taken w.r.t. values of #defines
3. Make sure the _headers versions also have the correct dependencies
Note: There are a few exceptions to 1. for some non code libraries like pico_standard_link and pico_cxx_options
* Remove unnecessary wait in pico_divider.
There is no need to wait if there is more than 8 cycles between setup and result readout.
Dividend/divisor readout should be correct without delay. Update comment to reflect that.
* Optimize hw_divider_save_state/hw_divider_restore_state.
Doing multiple pushes to avoid stack usage is faster.
The wait loop in hw_divider_save_state had an incorrect branch in the wait loop.
This didn't matter since the wait wasn't necessary to begin with.
* Remove pointless aligns in hardware_divider.
The regular_func_with_section inserts a new section so if aligning
is desired it should be placed in the macro after section start.
* Save a few bytes in hardware_divider.
Signed and unsigned code can use the same exit code.
Branching to the common code is free since we need the 8 cycle
delay anyway.
- The divider state needs to be saved for __aeabi_ddiv, __aeabi_fdiv, __aeabi_dtan and __aeabi_ftan or they won't work in interrupts *(probably not used much youd hope), or on an RTOS context switch
- Refactored code out for the integer and floating point cases
- Improved the floating point 'tests' in passing to check more return values against GCC implementations
- Added floating point usage to the IRQ nesting test case
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.
