Remove 'inline' attributes from static functions in .c files (#11426)

Let the compiler perform inlining (see #11397).

src/basic/hashmap.c

@@ -345,7 +345,7 @@ static unsigned base_bucket_hash(HashmapBase *h, const void *p) {
 }
 #define bucket_hash(h, p) base_bucket_hash(HASHMAP_BASE(h), p)
 
-static inline void base_set_dirty(HashmapBase *h) {
+static void base_set_dirty(HashmapBase *h) {
         h->dirty = true;
 }
 #define hashmap_set_dirty(h) base_set_dirty(HASHMAP_BASE(h))

src/basic/siphash24.c

@@ -23,13 +23,13 @@
 #include "siphash24.h"
 #include "unaligned.h"
 
-static inline uint64_t rotate_left(uint64_t x, uint8_t b) {
+static uint64_t rotate_left(uint64_t x, uint8_t b) {
         assert(b < 64);
 
         return (x << b) | (x >> (64 - b));
 }
 
-static inline void sipround(struct siphash *state) {
+static void sipround(struct siphash *state) {
         assert(state);
 
         state->v0 += state->v1;

src/basic/user-util.c

@@ -87,7 +87,7 @@ char *getusername_malloc(void) {
         return uid_to_name(getuid());
 }
 
-static inline bool is_nologin_shell(const char *shell) {
+static bool is_nologin_shell(const char *shell) {
 
         return PATH_IN_SET(shell,
                            /* 'nologin' is the friendliest way to disable logins for a user account. It prints a nice