license: update text

hci_transport: extract convenience function declaration for h4, h5, em9304_spi, and usb into separate hci_transport_{type}.h

MISRAC2012-Rule-10.4_a: append 'u' to constant literals when used in unsigned expressions or comparisons

hci_transport_em9304_spi: avoid spi read for empty payload

MISRAC2012-Rule-8.9: inline const objects that are used by single function

MISRAC2012-Rule-14.4_d: use while(true) instead of while(1)

ignore memcpy return value (always returns first parameter)

fix compile warnings (unused param, signed / unsigned comparison)

hci transport h4/h5/em9304: ignore block read/sent from UART driver when closed

hci_transport_em9304: fix payload size check

hci_transport_h4: fix payload size check

Use BTSTACK_FILE__ without __ prefix (MISRAC2012-Rule-21.1)

hci_transport_h4, hci_transport_em9304_spi.c: add checks for Event + SCO packet lengths

Replaced HCI_PACKET_BUFFER_SIZE with HCI_INCOMING_PACKET_BUFFER_SIZE and HCI_OUTGOING_PACKET_BUFFER_SIZE

em9304: fix RDY->RX transition

em9304: enforce 4-byte alignment on SPI operations

em9304: process all received data at once, cleanup state machine

em9304: change interface to provide callback on data available

em9304: add hci_transport_em9304_spi.c