rgbmatrix: recover gracefully from allocation errors

e.g., allocating a 192x32x6bpp matrix would be enough to trigger this
reliably on a Metro M4 Express using the "memory hogging" layout.
Allocating 64x32x6bpp could trigger it, but somewhat unreliably.

There are several things going on here:
 * we make the failing call with interrupts off
 * we were throwing an exception with interrupts off
 * protomatter failed badly in _PM_free when it was partially-initialized

Incorporate the fix from protomatter, switch to a non-throwing malloc
variant, and ensure that interrupts get turned back on.

This decreases the quality of the MemoryError (it cannot report the size
of the failed allocation) but allows CircuitPython to survive, rather
than faulting.

1 files changed, 0 insertions, 0 deletions

diff --git a/lib/protomatter b/lib/protomatter
-Subproject 761d6437e8cd6a131d51de96974337121a9c716
+Subproject 2a1ba8fa4753b2bcb158c9b17351cf18eade0d2