fix(examples): add C++ linkage guards to mcpwm foc svpwm example headers

Closes https://github.com/espressif/esp-idf/issues/19031

examples/peripherals/mcpwm/mcpwm_foc_svpwm_open_loop/main/foc/esp_foc.h

@@ -3,6 +3,8 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
+#pragma once
+
 #include <math.h>
 
 // Use IQ18 type, range [-8,192 8,191.999 996 185]
@@ -10,6 +12,10 @@
 #define GLOBAL_IQ               18
 #include "IQmathLib.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 // 3-phase uvw coord data type
 typedef struct foc_uvw_coord {
     _iq u;      // U phase data in IQ type
@@ -70,3 +76,7 @@ void foc_inverse_park_transform(_iq theta_rad, const foc_dq_coord_t *v_dq, foc_a
  * @param out_uvw[out]  output modulated pwm duty in IQ type
  */
 void foc_svpwm_duty_calculate(const foc_ab_coord_t *v_ab, foc_uvw_coord_t *out_uvw);
+
+#ifdef __cplusplus
+}
+#endif

examples/peripherals/mcpwm/mcpwm_foc_svpwm_open_loop/main/svpwm/esp_svpwm.h

@@ -4,8 +4,14 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#pragma once
+
 #include "driver/mcpwm_prelude.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * @brief   svpwm inverter config struct type
  */
@@ -78,3 +84,7 @@ esp_err_t svpwm_inverter_set_duty(inverter_handle_t handle, uint16_t u, uint16_t
  *          - ESP_ERR_INVALID_ARG: NULL arguments
  */
 esp_err_t svpwm_del_inverter(inverter_handle_t handle);
+
+#ifdef __cplusplus
+}
+#endif