pwm3360 driver cleanup and diff reduction to adns9800 (#15559)

* Diff reduction between ADNS9800 and PMW3360 drivers.

They are very similar devices. This (somewhat) unreadable diff is
essentially a no-op, but it makes a `vimdiff` between the 2 drivers much
more readable.

* Cleanup pwm3360 driver some more.

Remove redundant calls to spi_start() and spi_stop(), as pmw3360_write()
will already call these.

drivers/sensors/adns9800.c

@@ -77,7 +77,9 @@
 #define MSB1              0x80
 // clang-format on
 
-void adns9800_spi_start(void) { spi_start(ADNS9800_CS_PIN, false, ADNS9800_SPI_MODE, ADNS9800_SPI_DIVISOR); }
+void adns9800_spi_start(void) {
+    spi_start(ADNS9800_CS_PIN, false, ADNS9800_SPI_MODE, ADNS9800_SPI_DIVISOR);
+}
 
 void adns9800_write(uint8_t reg_addr, uint8_t data) {
     adns9800_spi_start();
@@ -154,8 +156,8 @@ void adns9800_init() {
 }
 
 config_adns9800_t adns9800_get_config(void) {
-    uint8_t config_1 = adns9800_read(REG_Configuration_I);
-    return (config_adns9800_t){(config_1 & 0xFF) * CPI_STEP};
+    uint8_t cpival = adns9800_read(REG_Configuration_I);
+    return (config_adns9800_t){(cpival & 0xFF) * CPI_STEP};
 }
 
 void adns9800_set_config(config_adns9800_t config) {
@@ -164,8 +166,8 @@ void adns9800_set_config(config_adns9800_t config) {
 }
 
 uint16_t adns9800_get_cpi(void) {
-    uint8_t config_1 = adns9800_read(REG_Configuration_I);
-    return (uint16_t){(config_1 & 0xFF) * CPI_STEP};
+    uint8_t cpival = adns9800_read(REG_Configuration_I);
+    return (uint16_t)(cpival & 0xFF) * CPI_STEP;
 }
 
 void adns9800_set_cpi(uint16_t cpi) {
@@ -184,7 +186,7 @@ static int16_t convertDeltaToInt(uint8_t high, uint8_t low) {
 }
 
 report_adns9800_t adns9800_get_report(void) {
-    report_adns9800_t report = {0, 0};
+    report_adns9800_t report = {0};
 
     adns9800_spi_start();