Fix a few warnings.

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@2774

src/cpu/core_dyn_x86.cpp

@@ -165,7 +165,7 @@ static struct {
 	Bit32u readdata;
 } core_dyn;
 
-struct {
+static struct {
 	Bit32u		state[32];
 	FPU_P_Reg	temp,temp2;
 	Bit32u		dh_fpu_enabled;

src/cpu/core_dyn_x86/cache.h

@@ -531,4 +531,4 @@ static void cache_close(void) {
 	cache_code = NULL;
 	cache_code_link_blocks = NULL;
 	cache_initialized = false; */
-}
+}