aggresive optimisation can replace occurrences of sinl() and cosl() with
sincosl(), but sincosl() is missing in newlib which causes error. So let's
use custom implementation here.
Signed-off-by: p-szafonimateusz <p-szafonimateusz@xiaomi.com>
Fix an issue that math library header files are not exported by make export.
Create symbolic links of libmcs, newlib and openlibm header to nuttx/include.
When we are using newlib as libm, we can consider newlib-esp32 for esp32
hardware. An it contains some optimization for esp32 hardware.
Besides, two small issues has been fixed.
1. add the tar ball to .gitignore
2. Fix the some build warnings
