Clarify DCMotor sample pin numbering and H-bridge wiring

[Copilot]

The DCMotor sample uses DCMotor.Create(6, 27, 22) but never documents that these are BCM (logical) GPIO numbers, nor which argument maps to which H-bridge input — making it impossible to wire the H-bridge to match the code. The maintainer confirmed the pins are BCM numbering.

Documentation/comment-only change; no motor control logic touched.

Changes

• README.md: Added a Wiring section stating pins use BCM numbering (with a link to the Raspberry Pi pinout), plus a table mapping each Create argument to its BCM pin and H-bridge input, and the remaining wiring notes as a bullet list. Kept the embedded code block in sync with the sample.
• samples/Program.cs: Added comments noting BCM numbering and the pin→H-bridge mapping, pointing to the README.

Pin mapping (3-pin mode)

Create argument	BCM pin	H-bridge input
speedControlPin	6	ENA (enable/PWM)
directionPin	27	IN1
otherDirectionPin	22	IN2

Note: the Fritzing diagram (dcmotor_bb.png) was not regenerated; the docs now explicitly state the numbering scheme so the code and diagram can be reconciled by a reviewer with the hardware.

[raffaeler]

I approved, but don´t know this piece of hardware.
Is there anyone that knows if the mappings are good?

[Copilot]

Pull request overview

Clarifies the DCMotor sample’s GPIO numbering scheme and documents how the DCMotor.Create(6, 27, 22) arguments map to typical H-bridge control inputs, so readers can wire hardware to match the sample.

Changes:

• Added BCM/GPIO numbering guidance and a pin-to-H-bridge mapping comment in the sample program.
• Added a new Wiring section in the DCMotor README with a mapping table and wiring notes.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
src/devices/DCMotor/samples/Program.cs	Adds comments explaining BCM numbering and the 3-pin wiring mapping.
src/devices/DCMotor/README.md	Adds a Wiring section with BCM numbering guidance, mapping table, and wiring checklist.