doc: printf() codes: Fix format specifier for unsigned int

The format specifier for the "unsigned int" variable is documented as
"%d". However, it should be "%u". Thus, fix it.

Fixes: f5e9035043fb ("doc: printf() codes")
Reported-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/doc/develop/printf.rst b/doc/develop/printf.rst
index 7b9aea0..99d0506 100644
--- a/doc/develop/printf.rst
+++ b/doc/develop/printf.rst
@@ -105,19 +105,19 @@
 =================== ==================
 Type                Format specifier
 =================== ==================
-bool		    %d, %x
+bool                %d, %x
 char                %d, %x
 unsigned char       %u, %x
 short               %d, %x
 unsigned short      %u, %x
 int                 %d, %x
-unsigned int        %d, %x
+unsigned int        %u, %x
 long                %ld, %lx
 unsigned long       %lu, %lx
 long long           %lld, %llx
 unsigned long long  %llu, %llx
 off_t               %llu, %llx
-ptr_diff_t	    %td, %tx
+ptr_diff_t          %td, %tx
 fdt_addr_t          %pa, see pointers
 fdt_size_t          %pa, see pointers
 phys_addr_t         %pa, see pointers