feat: implement PCI subsystem and integrate uACPI support

See previous commit

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

src/string.h

@@ -9,4 +9,5 @@ char* strncpy(char* dst, const char* src, size_t n);
 char* strcat(char* dst, const char* src);
 int strncmp(const char* a, const char* b, size_t n);
 wchar_t* utf16_to_codepoint(wchar_t* string, int* codepoint);
-char* codepoint_to_utf8(int codepoint, char* stringOutput);
+char* codepoint_to_utf8(int codepoint, char* stringOutput);
+size_t strnlen(const char* str, size_t maxlen);