firmware: qcom: scm: remove unneeded 'extern' specifiers

'extern' specifiers do nothing for function declarations. Remove them
from the private qcom-scm header.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Tested-by: Andrew Halaney <ahalaney@redhat.com> # sc8280xp-lenovo-thinkpad-x13s
Link: https://lore.kernel.org/r/20231017092732.19983-4-brgl@bgdev.pl
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Author: Bartosz Golaszewski

drivers/firmware/qcom/qcom_scm.h

@@ -66,18 +66,17 @@ int qcom_scm_wait_for_wq_completion(u32 wq_ctx);
 int scm_get_wq_ctx(u32 *wq_ctx, u32 *flags, u32 *more_pending);
 
 #define SCM_SMC_FNID(s, c)	((((s) & 0xFF) << 8) | ((c) & 0xFF))
-extern int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,
-			  enum qcom_scm_convention qcom_convention,
-			  struct qcom_scm_res *res, bool atomic);
+int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,
+		   enum qcom_scm_convention qcom_convention,
+		   struct qcom_scm_res *res, bool atomic);
 #define scm_smc_call(dev, desc, res, atomic) \
 	__scm_smc_call((dev), (desc), qcom_scm_convention, (res), (atomic))
 
 #define SCM_LEGACY_FNID(s, c)	(((s) << 10) | ((c) & 0x3ff))
-extern int scm_legacy_call_atomic(struct device *dev,
-				  const struct qcom_scm_desc *desc,
-				  struct qcom_scm_res *res);
-extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
+int scm_legacy_call_atomic(struct device *dev, const struct qcom_scm_desc *desc,
 			   struct qcom_scm_res *res);
+int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
+		    struct qcom_scm_res *res);
 
 #define QCOM_SCM_SVC_BOOT		0x01
 #define QCOM_SCM_BOOT_SET_ADDR		0x01