lib: Rename string.x to sbi_string.x

All string functions are part of libsbi. It makes more sense
to rename them to sbi_string.x as the libsbi can be linked
with external libraries that can have similar implementation.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>

lib/sbi/sbi_fifo.c

@@ -10,7 +10,7 @@
 #include <sbi/riscv_locks.h>
 #include <sbi/sbi_error.h>
 #include <sbi/sbi_fifo.h>
-#include <sbi/string.h>
+#include <sbi/sbi_string.h>
 
 void sbi_fifo_init(struct sbi_fifo *fifo, void *queue_mem, u16 entries,
 		   u16 entry_size)
@@ -20,7 +20,7 @@ void sbi_fifo_init(struct sbi_fifo *fifo, void *queue_mem, u16 entries,
 	fifo->entry_size  = entry_size;
 	SPIN_LOCK_INIT(&fifo->qlock);
 	fifo->avail = fifo->tail = 0;
-	memset(fifo->queue, 0, entries * entry_size);
+	sbi_memset(fifo->queue, 0, entries * entry_size);
 }
 
 /* Note: must be called with fifo->qlock held */
@@ -76,7 +76,7 @@ static inline void __sbi_fifo_reset(struct sbi_fifo *fifo)
 {
 	fifo->avail = 0;
 	fifo->tail  = 0;
-	memset(fifo->queue, 0, fifo->num_entries * fifo->entry_size);
+	sbi_memset(fifo->queue, 0, fifo->num_entries * fifo->entry_size);
 }
 
 bool sbi_fifo_reset(struct sbi_fifo *fifo)
@@ -149,7 +149,7 @@ int sbi_fifo_enqueue(struct sbi_fifo *fifo, void *data)
 	if (head >= fifo->num_entries)
 		head = head - fifo->num_entries;
 
-	memcpy(fifo->queue + head * fifo->entry_size, data, fifo->entry_size);
+	sbi_memcpy(fifo->queue + head * fifo->entry_size, data, fifo->entry_size);
 
 	fifo->avail++;
 
@@ -170,7 +170,7 @@ int sbi_fifo_dequeue(struct sbi_fifo *fifo, void *data)
 		return SBI_ENOENT;
 	}
 
-	memcpy(data, fifo->queue + (u32)fifo->tail * fifo->entry_size,
+	sbi_memcpy(data, fifo->queue + (u32)fifo->tail * fifo->entry_size,
 	       fifo->entry_size);
 
 	fifo->avail--;