Fix declaration of ica_aes_gcm_kma_ctx_new in ica_api.h header

When building an application that includes ica_api.h with -Wstrict-prototypes,
then this shows warnings/errors for the ica_aes_gcm_kma_ctx_new() declaration
in ica_api.h.

The declaration in ica_api.h is anyway different that the one used in
ica_api.c:

ica_api.h:
  ICA_EXPORT
  kma_ctx* ica_aes_gcm_kma_ctx_new();

ica_api.c:
  kma_ctx* ica_aes_gcm_kma_ctx_new(void)

Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>

Author: ifranzki

include/ica_api.h

@@ -3370,7 +3370,7 @@ typedef struct kma_ctx_t kma_ctx;
  * NULL if no memory could be allocated.
  */
 ICA_EXPORT
-kma_ctx* ica_aes_gcm_kma_ctx_new();
+kma_ctx* ica_aes_gcm_kma_ctx_new(void);
 
 /**
  * Initialize the GCM context. This description applies to both,