Replace db array default values with real literals

The default values for the database transfer functions were incorrectly
assiged as integer literals, recast to types using real32/64 but
actually corresponding to whatever integer kind equals real32/64.

We now simply assign it a literal value of -1. and rely on the compiler
to handle the recasting.

Although none of these functions were intended to be used, and -1 would
probably be eventually cast into an appropriate real type, it is better
to get this correct.

Thanks to Keith Lindsay for suggesting this change.

config_src/external/database_comms/database_client_interface.F90

@@ -317,7 +317,7 @@ function unpack_tensor_float_1d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:) = -1_real32
+    data(:) = -1.
   end function unpack_tensor_float_1d
 
   !> Unpack a 32-bit real 2d tensor from the database
@@ -329,7 +329,7 @@ function unpack_tensor_float_2d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:,:) = -1_real32
+    data(:,:) = -1.
   end function unpack_tensor_float_2d
 
   !> Unpack a 32-bit real 3d tensor from the database
@@ -341,7 +341,7 @@ function unpack_tensor_float_3d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:,:,:) = -1_real32
+    data(:,:,:) = -1.
   end function unpack_tensor_float_3d
 
   !> Unpack a 32-bit real 4d tensor from the database
@@ -353,7 +353,7 @@ function unpack_tensor_float_4d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:,:,:,:) = -1_real32
+    data(:,:,:,:) = -1.
   end function unpack_tensor_float_4d
 
   !> Unpack a 64-bit real 1d tensor from the database
@@ -365,7 +365,7 @@ function unpack_tensor_double_1d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:) = -1_real64
+    data(:) = -1.
   end function unpack_tensor_double_1d
 
   !> Unpack a 64-bit real 2d tensor from the database
@@ -377,7 +377,7 @@ function unpack_tensor_double_2d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:,:) = -1_real64
+    data(:,:) = -1.
   end function unpack_tensor_double_2d
 
   !> Unpack a 64-bit real 3d tensor from the database
@@ -389,7 +389,7 @@ function unpack_tensor_double_3d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:,:,:) = -1_real64
+    data(:,:,:) = -1.
   end function unpack_tensor_double_3d
 
   !> Unpack a 64-bit real 4d tensor from the database
@@ -401,7 +401,7 @@ function unpack_tensor_double_4d(self, name, data, dims) result(code)
     integer                           :: code
 
     code = -1
-    data(:,:,:,:) = -1_real64
+    data(:,:,:,:) = -1.
   end function unpack_tensor_double_4d
 
   !> Unpack a 32-bit integer 1d tensor from the database