Remove deprecated features

[haslinghuis]

Fixes: #3266

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
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No Coverage information
0.0% Duplication

[github-actions]

Do you want to test this code? Here you have an automated build:
Betaflight-Configurator-Android
Betaflight-Configurator-Linux
Betaflight-Configurator-macOS
Betaflight-Configurator-Windows
WARNING: It may be unstable and result in corrupted configurations or data loss. Use only for testing!

[haslinghuis]

typedef enum {
FEATURE_RX_PPM = 1 << 0,
FEATURE_INFLIGHT_ACC_CAL = 1 << 2,
FEATURE_RX_SERIAL = 1 << 3,
FEATURE_MOTOR_STOP = 1 << 4,
FEATURE_SERVO_TILT = 1 << 5,
FEATURE_SOFTSERIAL = 1 << 6,
FEATURE_GPS = 1 << 7,
FEATURE_RANGEFINDER = 1 << 9,
FEATURE_TELEMETRY = 1 << 10,
FEATURE_3D = 1 << 12,
FEATURE_RX_PARALLEL_PWM = 1 << 13,
FEATURE_RX_MSP = 1 << 14,
FEATURE_RSSI_ADC = 1 << 15,
FEATURE_LED_STRIP = 1 << 16,
FEATURE_DASHBOARD = 1 << 17,
FEATURE_OSD = 1 << 18,
FEATURE_CHANNEL_FORWARDING = 1 << 20,
FEATURE_TRANSPONDER = 1 << 21,
FEATURE_AIRMODE = 1 << 22,
FEATURE_RX_SPI = 1 << 25,
//FEATURE_SOFTSPI = 1 << 26, (removed)
FEATURE_ESC_SENSOR = 1 << 27,
FEATURE_ANTI_GRAVITY = 1 << 28,
//FEATURE_DYNAMIC_FILTER = 1 << 29, (removed)
} features_e;

[blckmn]

AUTOMERGE: (FAIL)

• github identifies PR as mergeable -> FAIL
• assigned to a milestone -> PASS
• cooling off period lapsed -> FAIL
• commit count less or equal to three -> PASS
• Don't merge label NOT found -> PASS
• at least one RN: label found -> PASS
• Tested label found -> FAIL
• assigned to an approver -> PASS
• approver count at least three -> FAIL

[nerdCopter]

• approved
• may break older 3.x and below which is understood to be no longer supported in 10.9, IIRC.